tag:blogger.com,1999:blog-41381022959758196102024-03-27T16:53:47.416-07:00MakeTheBrainHappyMakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.comBlogger189125tag:blogger.com,1999:blog-4138102295975819610.post-38515601543178081482024-01-05T16:00:00.000-08:002024-01-05T16:00:09.982-08:00Ski Patrol Trail Condition Questions<p> </p><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjWVK9-3EZKs3hw9mWFp_JmrL_Mn8EGMGdwZSd5QmdldfNAERdJrwUF-Gf73wQNWZLfR-I5g9uFaYsyL6c9erkYOoKkZHTcWdK3RWjy11kGbp-6YO84xGXnCSQyoVpq572mcHERUzb7ce0HSufvBC475ydsqu7tycXtfQ7jecSbik3rPv7sgIlckAVzOgU/s4032/IMG_4819.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="3024" data-original-width="4032" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjWVK9-3EZKs3hw9mWFp_JmrL_Mn8EGMGdwZSd5QmdldfNAERdJrwUF-Gf73wQNWZLfR-I5g9uFaYsyL6c9erkYOoKkZHTcWdK3RWjy11kGbp-6YO84xGXnCSQyoVpq572mcHERUzb7ce0HSufvBC475ydsqu7tycXtfQ7jecSbik3rPv7sgIlckAVzOgU/s320/IMG_4819.jpg" width="320" /></a></div><div class="separator" style="clear: both; text-align: center;">Figure 1: Ski Slope, Full View Uphill</div><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhbjn85ynd3LS-308cAF6jIyORbaFpViXoy6UpILCuVwuUjJFm_QXBb5_g3cY5yA5mohMN6HjLURbfiE1aYOeBMKJ5Vej2xf_Aq71f9oNdbbSAZ3i8TVmGNVb09jfhTrsGTGzpQN0iFE2kKmm8lkSEgCJRakPjUylpyG0wamBj97LMINvP14Jy4wn38adE/s4032/IMG_4822.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="3024" data-original-width="4032" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhbjn85ynd3LS-308cAF6jIyORbaFpViXoy6UpILCuVwuUjJFm_QXBb5_g3cY5yA5mohMN6HjLURbfiE1aYOeBMKJ5Vej2xf_Aq71f9oNdbbSAZ3i8TVmGNVb09jfhTrsGTGzpQN0iFE2kKmm8lkSEgCJRakPjUylpyG0wamBj97LMINvP14Jy4wn38adE/s320/IMG_4822.jpg" width="320" /></a></div><div class="separator" style="clear: both; text-align: center;">Figure 2: Marking, Skier's Left</div><br /><div class="separator" style="clear: both; text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh5n28IDYC-6EZrfHAPaOy3GLGUNvprIYhJF-Q-WuPUSNFsGoTg7a9z3V7pVEvpb10foWebQpIyeBe0SjbTZd-Qpa8HtfEcqUfEMDniDZjPP7iaw_hhgIG6UKTXtcVTOVRltyO84byh-scFxtnb9kVg7yjTDxyO0jVnn0j8XDlLu8qAlQVuKIbMis6QaTI/s4032/IMG_4821.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="3024" data-original-width="4032" height="240" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh5n28IDYC-6EZrfHAPaOy3GLGUNvprIYhJF-Q-WuPUSNFsGoTg7a9z3V7pVEvpb10foWebQpIyeBe0SjbTZd-Qpa8HtfEcqUfEMDniDZjPP7iaw_hhgIG6UKTXtcVTOVRltyO84byh-scFxtnb9kVg7yjTDxyO0jVnn0j8XDlLu8qAlQVuKIbMis6QaTI/s320/IMG_4821.jpg" width="320" /></a></div><div class="separator" style="clear: both; text-align: center;">Figure 3: Marking, Skier's Right</div><div class="separator" style="clear: both; text-align: center;"><br /></div><div class="separator" style="clear: both; text-align: left;">The ski slope is marked as shown in <b>Figures 1-3</b>. </div><div class="separator" style="clear: both; text-align: left;"><br /></div><p></p><ol><li><p>When assessing the risk of hypothermia in the depicted environment, which factor is most critical?
A. Wind chill <br />B. Proximity to a heat source
<br />C. Time of day
<br />D. Visibility
<br />E. Wildlife activity</p></li><li><p>Considering avalanche safety, which of the following should be regularly checked in such an environment?
<br />A. Snowpack stability
<br />B. Forecasted temperatures
<br />C. Pathway obstructions
<br />D. Wildlife migration patterns
<br />E. Trail markers</p></li><li><p>What is the primary concern for ski patrol when the snow on the trees is as heavy as shown?<br />A. Ensuring visibility of trail markers<br />B. Monitoring for signs of tree falls<br />C. Clearing pathways of snow<br />D. Checking for frozen lakes<br />E. Patrolling for lost skiers</p></li><li><p>Given the conditions shown, what is the most likely cause of a trail closure?
<br />A. Ice formation on the path
<br />B. Low visibility due to fog
<br />C. Snow overload on branches
<br />D. Inaccessibility due to heavy snowfall
<br />E. Daylight limitations</p></li><li><p>Which of these is an essential communication tool for teams in such remote and snowy conditions?
A. Mobile phone
<br />B. Two-way radio
<br />C. Public address system
<br />D. Satellite phone
<br />E. Megaphone</p></li><li><p>When marking hazards on the trail, what characteristic of the markers is most crucial?
<br />A. Height above the snow
<br />B. Color contrast with the environment
<br />C. Frequency along the trail
<br />D. Reflectiveness
<br />E. Size of the marker</p></li><li><p>What environmental change should be most closely monitored to prevent hypothermia and frostbite in patrollers?
<br />A. Snow density
<br />B. Ambient temperature
<br />C. Humidity levels
<br />D. Wind speed
<br />E. Barometric pressure</p></li><li><p>For patrollers conducting a search operation, what is the most significant terrain challenge indicated by the images?
<br />A. Steep inclines
<br />B. Open crevasses
<br />C. Dense forest areas
<br />D. Snow-covered paths
<br />E. Icy patches</p></li><li><p>During end-of-day checks, what is a key environmental sign that patrollers should report?
<br />A. Decreasing temperatures
<br />B. Changes in snow texture
<br />C. Animal tracks
<br />D. Partially covered trail markers
<br />E. Melting snow around water bodies</p></li></ol><div class="separator" style="clear: both;"><p>Answers:</p><ol><li>A</li><li>A</li><li>B</li><li>D</li><li>B</li><li>B</li><li>B</li><li>C</li><li>D</li></ol></div><p><br /></p>MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com1tag:blogger.com,1999:blog-4138102295975819610.post-1803765403176338302021-07-03T09:08:00.000-07:002021-07-03T09:08:19.244-07:00Techniques of Partial Fraction DecompositionPartial fraction decomposition is very often used for many applications, such as <a href="https://en.wikipedia.org/wiki/Partial_fraction_decomposition#Application_to_symbolic_integration">integration of rational fractions</a>, <a href="https://en.wikipedia.org/wiki/Laplace_transform">inverse Laplace transforms</a>, and <a href="https://en.wikipedia.org/wiki/Taylor_series">Taylor series expansions</a>. In this article, we skip discussions on the basics of partial fraction decomposition in view of many other resources online, however we do highlight techniques to efficiently decompose a fraction into partial fractions.<br />
<ul>
<li><a href="he0">Factorization of Polynomials to Linear/Quadratic Factors</a></li>
<li><a href="he1">Method of Undetermined Coefficients</a></li>
<li><a href="he2">Substitution Method</a></li>
<li><a href="he3">Multiplication Method</a></li>
<li><a href="he4">Heaviside Cover-up Method</a></li>
<li><a href="he5">Partial Fraction Decomposition through Mathematical Software</a></li>
<li><a href="he6">Problems</a></li>
</ul><br />
Before we start, we emphasize not to forget the following steps before decomposing the fraction:
<div>
<ol style="text-align: left;">
<li>Ensure the numerator and denominator are both polynomials.</li>
<li>Ensure the numerator of the fraction has an order less than the denominator.</li>
<li>Ensure the denominator is completely reduced to irreducible factors.</li>
</ol>
</div>
We direct the reader to <a href="https://www.mesacc.edu/~scotz47781/mat120/notes/divide_poly/long_division/long_division.html">a document</a> on how to divide polynomials. A table of the decomposition of a fraction of rational functions is provided below.
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<div class="tg-wrap"><table class="tg">
<thead>
<tr>
<th class="tg-7btt">Irreducible factor in denominator</th>
<th class="tg-7btt">Term in decomposition</th>
</tr>
</thead>
<tbody>
<tr>
<td class="tg-c3ow">$ax+b$</td>
<td class="tg-c3ow">$\frac{C_1}{ax+b}$</td>
</tr>
<tr>
<td class="tg-c3ow">$(ax+b)^n$</td>
<td class="tg-c3ow">$\frac{C_1}{ax+b}+\frac{C_2}{(ax+b)^2}+...+\frac{C_n}{(ax+b)^n}$</td>
</tr>
<tr>
<td class="tg-c3ow">$ax^2+bx+c$</td>
<td class="tg-c3ow">$\frac{C_1x+D_1}{ax^2+bx+c}$</td>
</tr>
<tr>
<td class="tg-c3ow">$(ax^2+bx+c)^n$</td>
<td class="tg-c3ow">$\frac{C_1x+D_1}{ax^2+bx+c}+\frac{C_2x+D_2}{(ax^2+bx+c)^2}+...+\frac{C_nx+D_n}{(ax^2+bx+c)^n}$</td>
</tr>
</tbody>
</table></div>
The table above does not include factors of higher order since all higher polynomials must be converted to a multiple of irreducible factors located in the table. This procedure is described below.<br /><br />
<div><h2 id="he0" style="text-align: left;">Factorization of Polynomials to Linear/Quadratic Factors</h2><div>
Any polynomial can be represented by the product of irreducible, real linear and quadratic factors. This is the result of the <a href="https://en.wikipedia.org/wiki/Fundamental_theorem_of_algebra">fundamental theorem of algebra</a>. The factorization of the rational denominator is required before partial fraction decomposition can commence. There are a few methods to do so, involving the <a href="https://en.wikipedia.org/wiki/Rational_root_theorem">rational root theorem</a> to find linear factors with rational roots. However, this is somewhat restrictive. A more general method for factorizing any polynomial is to first solve (often graphically) for the roots to find the linear factors. After dividing the polynomial by all determined linear factors, the remaining function should be a product of solely irreducible quadratics. The coefficients for the quadratics are found by solving a system of nonlinear equations. This method is best illustrated with a comprehensive example.<br /><br />
Example: Reduce the polynomial into irreducible linear and quadratic factors with real coefficients.
$$f(x)=2x^7-9x^6+31x^4-21x^3+24x^2-9x+54$$
At first, this looks extremely intimidating, but initial factorization is simple. Graph the polynomial and it is immediately obvious that two roots exist: $x=-2$ with a multiplicity of 1 and $x=3$ with a multiplicity of 2. Therefore, the linear factors, which are comprised of the real roots, are $x+2$ and $(x-3)^2$ (multiplicity is incorporated as a power). Long division of $f(x)$ with the product of the linear factors produces $g(x)=2x^4-x^3+2x^2+3$. With an order of 4, this function is therefore a product of two quadratics. We denote these two quadratics as:
\begin{align*}
ax^2+bx+c\\
ux^2+vx+w\end{align*}
Multiplying the two polynomials and setting it equal to $g(x)$ results in:
$$(au)x^4+(av+bu)x^3+(aw+bv+cu)x^2+(bw+cv)x+cw=2x^4-x^3+2x^2+3$$
Comparison of coefficients yields:
\begin{align*}
au&=2 \\
av+bu&=-1 \\
aw+bv+cu&=2 \\
bw+cv&=0 \\
cw&=3\end{align*}
There are five equations and six unknowns yielding one degree of freedom. We arbitratily set $a=1$ making $u=2$ through the first equation. With some algebra, it can be shown that there are two sets of polynomials that satisfy the equations above. One solution produces the two polynomials $x^2+x+1$ and $2x^2-3x+3$. So, the final answer is:
$$f(x)=(x-3)^2(x+2)(x^2+x+1)(2x^2-3x+3)$$
It is significantly easier to do this factorization through a mathematical software. MATLAB provides a function, <i>factor</i>, that can be used for this purpose.
<!--HTML generated using hilite.me--><div style="background: rgb(255, 255, 255); border-color: gray; border-image: initial; border-style: solid; border-width: 0.1em 0.1em 0.1em 0.8em; border: solid gray; color: black; overflow: auto; padding: 0.2em 0.6em; width: auto;"><pre style="line-height: 125%; margin: 0px;">syms x
F = <span style="color: #007020;">factor</span>(<span style="color: #0000dd; font-weight: bold;">2</span><span style="color: #333333;">*</span>x^<span style="color: #0000dd; font-weight: bold;">7</span><span style="color: #333333;">-</span><span style="color: #0000dd; font-weight: bold;">9</span><span style="color: #333333;">*</span>x^<span style="color: #0000dd; font-weight: bold;">6</span><span style="color: #333333;">+</span><span style="color: #0000dd; font-weight: bold;">31</span><span style="color: #333333;">*</span>x^<span style="color: #0000dd; font-weight: bold;">4</span><span style="color: #333333;">-</span><span style="color: #0000dd; font-weight: bold;">21</span><span style="color: #333333;">*</span>x^<span style="color: #0000dd; font-weight: bold;">3</span><span style="color: #333333;">+</span><span style="color: #0000dd; font-weight: bold;">24</span><span style="color: #333333;">*</span>x^<span style="color: #0000dd; font-weight: bold;">2</span><span style="color: #333333;">-</span><span style="color: #0000dd; font-weight: bold;">9</span><span style="color: #333333;">*</span>x<span style="color: #333333;">+</span><span style="color: #0000dd; font-weight: bold;">54</span>)
</pre></div>
Output:
<code>
F = [ x + 2, x^2 + x + 1, 2*x^2 - 3*x + 3, x - 3, x - 3]
</code><br /><br />
<div><h2 id="he1" style="text-align: left;">Method of Undetermined Coefficients</h2><div>
This method is often used as a fail-safe method for decomposing fractions. The unknown coefficients of the decomposed fractions are solved by forcing the partial fraction decomposition into a form synonymous with the original function. This function will have the same denominator as the original function, with unknown variables all in the numerator. The unknown coefficients are subsequently solved through comparing the two functions' numerators. Consider the function:
$$f(x)=\frac{4x^2+6x+6}{x^3-7x-6}$$
By factorizing the denominator through the method described <a href="he0">in the previous section</a>, we end up with the following:
$$f(x)=\frac{4x^2+6x+6}{(x-3)(x+1)(x+2)}$$
The partial fraction decomposition of the function, let's call $g(x)$, is:
$$g(x)=\frac{A}{x-3}+\frac{B}{x+1}+\frac{C}{x+2}$$
Note that we are solving for the unknown parameters $A,B,C$ to make $f(x)$ and $g(x)$ equal. First, combine the partial fractions into one fraction. This is done by first making the denominators of the individual partial fractions the same as the original function's denominator.
$$g(x)=\frac{A}{x-3} \times \frac{(x+1)(x+2)}{(x+1)(x+2)}+\frac{B}{x+1} \times \frac{(x-3)(x+2)}{(x-3)(x+2)}+\frac{C}{x+2} \times \frac{(x-3)(x+1)}{(x-3)(x+1)}$$
We've merely multiplied all the fractions by one, since the multiplying factors all have the same numerator and denominator.
$$g(x)=\frac{A(x+1)(x+2)}{(x-3)(x+1)(x+2)}+\frac{B(x-3)(x+2)}{(x-3)(x+1)(x+2)}+\frac{C(x-3)(x+1)}{(x-3)(x+1)(x+2)}$$
$$=\frac{A(x+1)(x+2)+B(x-3)(x+2)+C(x-3)(x+1)}{(x-3)(x+1)(x+2)}$$
At this point, comparing the numerator with the original function's numerator is not useful. We need to force it into the same rational form as the original function's numerator. Thus, we need to simplify the numerator into the form $c_1x^2+c_2x+c_3$. Fortunately this is relatively straightforward but requires some algebra:
$$g(x)=\frac{A(x^2+3x+2)+B(x^2-x-6)+C(x^2-2x-3)}{(x-3)(x+1)(x+2)}$$
$$=\frac{Ax^2+3Ax+2A+Bx^2-Bx-6B+Cx^2-2Cx-3C}{(x-3)(x+1)(x+2)}$$
$$=\frac{(A+B+C)x^2+(3A-B-2C)x+(2A-6B-3C)}{(x-3)(x+1)(x+2)}$$
The denominator of both functions $f(x)$ and $g(x)$ are the same, meaning that if the numerators are the same, then the two functions are equal!
$$(A+B+C)x^2+(3A-B-2C)x+(2A-6B-3C)=4x^2+6x+6$$
Now that both sides are in the same form, that is, a polynomial of order 2, all that is needed for the numerators to be the same is for the coefficient on the left side to match up with the coefficients on the right hand side. Let us represent this equality slightly differently:
\begin{alignat*}{2}(A+B+C)x^2&{}+{}&(3A-B-2C)x&{}+{}&(2A-6B-3C)\\=4x^2&{}+{}&6x&{}+{}&6\end{alignat*}
It is now evident that for the coefficients to match up:
\begin{alignat*}{2}&A&{}+{}&&B&{}+{}&&C&{}={}&4 \label{eq:1} \tag{1}\\
3&A&{}-{}&&B&{}-{}&2&C&{}={}&6 \label{eq:2} \tag{2}\\
2&A&{}-{}&6&B&{}-{}&3&C&{}={}&6 \label{eq:3} \tag{3}\end{alignat*}
The first step in solving this system is to subtract equation \ref{eq:2} by equation \ref{eq:3} then by \ref{eq:1} to get $B=-1$. Then multiply equation \ref{eq:1} by 2 and subtract \ref{eq:3} by \ref{eq:1}, yielding $C=2$. Plug in $B$ and $C$ into equation \ref{eq:1} to get $A=3$.
Therefore:
$$f(x)=\frac{3}{x-3}-\frac{1}{x+1}+\frac{2}{x+2}$$
This method of solving for the unknowns in the partial fraction decomposition works all the time for any sort of partial fraction decomposition. However it is clear that it requires a lot of algebra and thus there is a greater chance calculation errors may arise.<br /><br />
<div><h2 id="he2" style="text-align: left;">Substitution Method</h2><div>
Consider the previous function again and its partial fraction expansion:
$$\frac{4x^2+6x+6}{(x-3)(x+1)(x+2)}=\frac{A}{x-3}+\frac{B}{x+1}+\frac{C}{x+2}$$
It is important to realize that the equality above must hold for all values of $x$ in the original function's domain. Thus, by simply substituting three arbitrarily different values of $x$ into the equation above, we can derive a system of three equations of $A,B,C$ and solve accordingly. This results in a system of equations that is determined quicker than the previous Method of Undetermined Coefficients. However, a system of equations is still needing to be solved, and for large system of equations, this is very tedious. This method is rarely used to do a complete partial fraction decomposition, however it is used in conjunction with other methods and so the concept is important to understand.<br /><br />
<div><h2 id="he3" style="text-align: left;">Multiplication Method</h2><div>
This method solves for parameters without necessarily needing to solve systems.
Consider the previous function again and its partial fraction expansion:
$$\frac{4x^2+6x+6}{(x-3)(x+1)(x+2)}=\frac{A}{x-3}+\frac{B}{x+1}+\frac{C}{x+2}$$
To solve for $A$, multiply both sides of the equation above by the denominator $x-3$ associated with $A$. Take note that when $x=3, x-3$ is equal to zero.
$$\frac{4x^2+6x+6}{(x+1)(x+2)}=A+\frac{B(x-3)}{x+1}+\frac{C(x-3)}{x+2}$$
Now, set $x=3$ as previously found. Parameters $B$ and $C$ are now cancelled with the substitution as they are both multiplied by zero. While using this method, make sure there are no divisions by zero!
$$\frac{4(3)^2+6(3)+6}{(3+1)(3+2)}=A+\frac{B(3-3)}{3+1}+\frac{C(3-3)}{3+2}$$
$$\frac{60}{20}=A+0+0$$
$$\therefore A=3$$
Similarly, $B$ and $C$ are found the same way. <br />
Now, let's consider another more complicated partial fraction. Consider the function and its partial fraction expansion:
$$\frac{6x^2+9x+3}{(x-1)(x+2)^2}=\frac{A}{x-1}+\frac{B}{x+2}+\frac{C}{(x+2)^2} \label{eq:4} \tag{4}$$
$A$ can be found through this method. The steps for showing $A=2$ is omitted.
However, note we cannot solve for $B$ using this method. If we proceed to solve for $B$ using this method, we first need to multiply both sides by $x+2$.
$$\frac{6x^2+9x+3}{(x-1)(x+2)}=\frac{A(x+2)}{x-1}+B+\frac{C}{x+2}$$
If we substitute $x=-2$, we get a division by zero on the left and right-hand side. However, if we instead solve for $C$, multiplying both sides by $(x+2)^2$ yields:
$$\frac{6x^2+9x+3}{x-1}=\frac{A(x+2)^2}{x-1}+B(x+2)+C$$
Substituting $x=-2$ now works:
$$\frac{6(-2)^2+9(-2)+3}{-2-1}=\frac{A(-2+2)^2}{-2-1}+B(-2+2)+C$$
$$\therefore C=\frac{9}{-3}=-3$$
To solve for $B$, one may use the Method of Undetermined Coefficients, however it is easier in this case just to use the Substitution method and substitute one number into equation \ref{eq:4}. Any number that does not result in a division by zero can be substituted, so we substitute $x=-1$, which is the root of the numerator in the original function. Note this value is in the domain of the original function. There is no division by zero as a result and the left-hand side of equation \ref{eq:4} goes to zero:
$$0=\frac{A}{-1-1}+\frac{B}{-1+2}+\frac{C}{(-1+2)^2}$$
Values of $A$ and $C$ have already been solved using the Multiplication method.
$$0=\frac{2}{-1-1}+\frac{B}{-1+2}-\frac{3}{(-1+2)^2}$$
$$\therefore B=1+3=4$$
$$\frac{6x^2+9x+3}{(x-1)(x+2)^2}=\frac{2}{x-1}+\frac{4}{x+2}-\frac{3}{(x+2)^2}$$
<b>Therefore, for the partial fractions that result from repeated linear factors, the Multiplication Method should be used on the associated partial fraction with the denominator raised to the highest power. This method cannot be solely used to solve for the other factors raised to a lower power.</b><br />
For fractions where the denominator has quadratics or quadratic terms raised to a power, <i>all</i> unknown parameters can be calculated with this method since a division by zero is mitigated. However, the use of complex numbers is required. For example, observe the function and its decomposition below:
$$\frac{-x^2 + 3 x - 11}{(x - 2) (x^2 - 2 x + 3)}=\frac{A}{x-2}+\frac{Bx+C}{x^2-2x+3}$$
$A$ is solved easily to yield $A=-3$. To solve for $B$ and $C$, multiply both sides by $x^2-2x+3$.
$$\frac{-x^2 + 3 x - 11}{x - 2}=\frac{A(x^2-2x+3)}{x-2}+Bx+C$$
The roots to $x^2-2x+3$ are $1+i\sqrt{2}$ and $1-i\sqrt{2}$.<!--, so substitute both into the equation above and solve the system of equations.--> For the first root:
$$\frac{-(1+i\sqrt{2})^2+3(1+i\sqrt{2})-11}{1+i\sqrt{2}-2}=\frac{A(0)}{x-2}+B(1+i\sqrt{2})+C$$
$$\frac{-7+i\sqrt{2}}{-1+i\sqrt{2}}=B(1+i\sqrt{2})+C$$
$$3 + 2 i \sqrt{2}=B(1+i\sqrt{2})+C \label{eq:5} \tag{5}$$
At this point, we know $B$ and $C$ must be real numbers, so that automatically forces $B$ to equal 2. Then it follows that $C=1$.
<!--Similarly for the other root:
$$3 - 2 i \sqrt{2}=B(1-i\sqrt{2})+C \label{eq:6} \tag{6}$$
Take \ref{eq:5} and subtract it with \ref{eq:6} to get $4i\sqrt{2}=B(2i\sqrt{2})$ which yields $B=2$. Substitute this value back into \ref{eq:5} to get that $C=1$.--> A review of complex number operations is located <a href="https://www.dummies.com/education/math/calculus/how-to-perform-operations-with-complex-numbers/">here</a>.<br />
Complex number algebra may be a bit tedious so in this case, the Method of Undetermined Coefficients to solve for $B$ and $C$ may have produced a quicker answer. However, if a fraction has many linear factors in its denominator and only one or two quadratic terms, this method for partial fraction decomposition may be faster compared to the Method of Undetermined Coefficients since this method does not require the tedious step of combining all partial fractions into one fraction. <br />
With the same analysis, it can be shown that <b>for partial fractions that result from repeated quadratic factors, the Multiplication Method should be used on the associated partial fraction with the denominator raised to the highest power. This method cannot be solely used to solve for the other factors raised to a lower power.</b> This is the same conclusion as the case for repeated linear factors.<br /><br />
<div><h2 id="he4" style="text-align: left;">Heaviside Cover-up Method</h2><div>
The Heaviside Cover-up Method uses the exact method as the Multiplication Method, but removes the intermediate algebra steps to drastically improve the time in solving for the unknown coefficients. It is especially useful for a partial fraction decomposition of many terms. However, it is important that the Heaviside Method has the same requirements presented in the multiplication method; this method works all the time for a decomposition with only linear factors but special exceptions apply for decompositions with other types of factors.
Using the same example as before,
$$\frac{4x^2+6x+6}{(x-3)(x+1)(x+2)}=\frac{A}{x-3}+\frac{B}{x+1}+\frac{C}{x+2}$$
The decomposition only involved linear factors, and so the Heaviside Cover-up method will work to solve for all parameters. Now, to solve for $A$, first notice that the denominator associated with $A$ in the partial fraction equals zero when $x=3$. Next, we simply 'cover up' or remove the factor $x-3$ associated with $A$ in the original function.
$$\frac{4x^2+6x+6}{\hphantom{(x-3)}(x+1)(x+2)}$$
Lastly, we plug in the $x$ value of 3 that we previously solved for and plug it into the remaining function.
$$A=\frac{4(3)^2+6(3)+6}{\hphantom{(x-3)}(3+1)(3+2)}=3$$
Solving for $B$ this time, $x=-1$ to solve for the root of the denominator $x+1$ associated with $B$. Next, 'cover up' $x+1$ from the original function.
$$\frac{4x^2+6x+6}{(x-3)\hphantom{(x+1)}(x+2)}$$
Substitute $x=-1$ into the remaining function.
$$B=\frac{4(-1)^2+6(-1)+6}{(-1-3)\hphantom{(x+1)}(-1+2)}=-1$$
Solve $C$ through the same way.
$$C=\frac{4(-2)^2+6(-2)+6}{(-2-3)(-2+1)\hphantom{(x+2)}}=2$$
Now, for the case of non-linear factors in the denominator:
$$\frac{4x^2-x-2}{x^2(x-1)}=\frac{A}{x}+\frac{B}{x^2}+\frac{C}{x-1}$$
Heaviside method can be used for the fractions with linear denominators as was the case in the multiplication method.
$$C=\frac{4(1)^2-1-2}{(1)^2\hphantom{(x-1)}}=1$$
The Heaviside method can be used for the partial fraction with the highest order denominator that resulted from the $x^2$ term:
$$B=\frac{4(0)^2-0-2}{\hphantom{x^2}(0-1)}=2$$
The substitution method / method of undetermined coefficients is used to solve for the last unknown parameter. Selecting an arbitrary value to substitute $x=2$,
$$\frac{4(2)^2-2-2}{2^2(2-1)}=\frac{A}{2}+\frac{B}{2^2}+\frac{C}{2-1}$$
$$3=\frac{A}{2}+\frac{2}{2^2}+\frac{1}{1}$$
which quickly shows that $A=3$. A table is conveniently provided below to list out restrictions when using the Heaviside method.
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<thead>
<tr>
<th class="tg-7btt">Irreducible factor in denominator</th>
<th class="tg-7btt">Heaviside method restriction</th>
</tr>
</thead>
<tbody>
<tr>
<td class="tg-c3ow">$ax+b$</td>
<td class="tg-c3ow">None.</td>
</tr>
<tr>
<td class="tg-c3ow">$(ax+b)^n$</td>
<td class="tg-c3ow">May only be used on associated partial fraction with denominator raised to highest power.</td>
</tr>
<tr>
<td class="tg-c3ow">$ax^2+bx+c$</td>
<td class="tg-c3ow">None, complex numbers required. May be quicker to use Method of Undetermined Coefficients.</td>
</tr>
<tr>
<td class="tg-c3ow">$(ax^2+bx+c)^n$</td>
<td class="tg-c3ow">May only be used on associated partial fraction with denominator raised to highest power. Complex numbers required. May be quicker to use Method of Undetermined Coefficients.</td>
</tr>
</tbody>
</table></div><br /><br />
<div><h2 id="he5" style="text-align: left;">Partial Fraction Decomposition through Mathematical Software</h2><div>
Given the opportunity, this method is the easiest. MATLAB provides a function, <i>partfrac</i>, that can be used. The function accepts the function, and optionally the independent variable. For the same function given first in the Methods of Undetermined Coefficient method $\frac{4x^2+6x+6}{x^3-7x-6}$, the partial fraction is calculated through the code:
<!--HTML generated using hilite.me--><div style="background: rgb(255, 255, 255); border-color: gray; border-image: initial; border-style: solid; border-width: 0.1em 0.1em 0.1em 0.8em; border: solid gray; color: black; overflow: auto; padding: 0.2em 0.6em; width: auto;"><pre style="line-height: 125%; margin: 0px;">syms x
f=partfrac((<span style="color: #0000dd; font-weight: bold;">4</span><span style="color: #333333;">*</span>x^<span style="color: #0000dd; font-weight: bold;">2</span><span style="color: #333333;">+</span><span style="color: #0000dd; font-weight: bold;">6</span><span style="color: #333333;">*</span>x<span style="color: #333333;">+</span><span style="color: #0000dd; font-weight: bold;">6</span>)<span style="color: #333333;">/</span>(x^<span style="color: #0000dd; font-weight: bold;">3</span><span style="color: #333333;">-</span><span style="color: #0000dd; font-weight: bold;">7</span><span style="color: #333333;">*</span>x<span style="color: #333333;">-</span><span style="color: #0000dd; font-weight: bold;">6</span>))
</pre></div>
Output: <code>f = 2/(x + 2) - 1/(x + 1) + 3/(x - 3)</code><br />
Use the optional second parameter to specify the independent variable. In the case of $\frac{a}{(x+a)(x+2)}$, $x$ is the independent variable and $a$ is a constant:
<!--HTML generated using hilite.me--><div style="background: rgb(255, 255, 255); border-color: gray; border-image: initial; border-style: solid; border-width: 0.1em 0.1em 0.1em 0.8em; border: solid gray; color: black; overflow: auto; padding: 0.2em 0.6em; width: auto;"><pre style="line-height: 125%; margin: 0px;">syms x a
f=partfrac(a<span style="color: #333333;">/</span>((x<span style="color: #333333;">+</span>a)<span style="color: #333333;">*</span>(x<span style="color: #333333;">+</span><span style="color: #0000dd; font-weight: bold;">2</span>)),x)
</pre></div>
Output: <code>f = a/((a - 2)*(x + 2)) - a/((a + x)*(a - 2))</code><br /><br />
<div><h2 id="he6" style="text-align: left;">Problems</h2>
<div>
<ol style="text-align: left;">
<li>Decompose $f(x)=\frac{4x^2+6x+8}{x^2(x+4)}$ into partial fractions using all the methods shown.</li>
<li>Decompose $f(x)=\frac{a}{(x-b)(x-c)}$ into partial fractions, where $a,b,c$ are real numbers and $b \neq c$.</li>
</ol>
</div>
</div></div></div></div></div></div></div></div></div></div></div></div></div>KrIsMahttp://www.blogger.com/profile/11734355428711933497noreply@blogger.com6tag:blogger.com,1999:blog-4138102295975819610.post-53114367511079681832021-04-18T19:58:00.010-07:002023-07-25T08:10:05.736-07:00Is BaSO4 soluble or insoluble? <p><span style="font-size: large;">Answer: BaSO4 would typically be considered insoluble due to the presence of a sulfate ion. This usually precludes an ion from disassociating easily in an aqueous solution; this being water. </span></p><p>The idea of BaSO4 being considered insoluble is further borne out in the Ksp values. While these cannot be directly related to molar solubility, they provide a strong hint that <b>Barium sulfate</b> is more stringent than other comparable molecules. For example Ba(OH)2's ksp is approximately seven orders of magnitude less which means that it is much more likely to ionize. You can tell that the molar solubility of barium hydroxide is orders of magnitude greater without performing the necessary calculations. As a reminder a compound is considered insoluble if less than 1% of the compound ionizes. </p><table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-hhxJAbveQwE/YHzvrvQ0roI/AAAAAAAACRI/vgHIZrIQENkj8j5J8FvWaTOXvSN3ub9xQCLcBGAsYHQ/s1012/Barium%2BMolecules%2BKsp.png" style="margin-left: auto; margin-right: auto;"><img alt="Barium Products Ksp Values" border="0" data-original-height="306" data-original-width="1012" height="194" src="https://1.bp.blogspot.com/-hhxJAbveQwE/YHzvrvQ0roI/AAAAAAAACRI/vgHIZrIQENkj8j5J8FvWaTOXvSN3ub9xQCLcBGAsYHQ/w640-h194/Barium%2BMolecules%2BKsp.png" title="Barium Products Ksp Values" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">ksp values of some common Barium products (<a href="https://www.chm.uri.edu/weuler/chm112/refmater/KspTable.html">source</a>)</td></tr></tbody></table><p><b>What is the molar solubility of BaSO4?</b></p><p>The calculation is based on the chemical equation for the disassociation of BaSO4 and the formula for ksp (equilibrium constants only include aqueous and gaseous species). </p><p>BaSO₄(s) ⇌ Ba²⁺(aq) + SO₄²⁻(aq)</p><p>K_sp = [Ba²⁺][SO₄²⁻]</p><p>Since when we ionize we create the two ions in equal molar quantity we can state the following</p><p>[Ba²⁺] = [SO₄²⁻] = x</p><p>$1.1*10^-10 = x^2$</p><p>x = $1.05*10^-5$ M</p><p>This concentration indicates that less than 1% of the solution is composed of ionized species. </p><p><b>How does BaSO4 theoretically ionize? </b></p><p>As the equation (BaSO4 (s) => Ba(2+)(aq) + SO4(2-)(aq)) indicates, barium sulfate would disassociate and produce the barium and sulfate ion. In the real world; however, the low molar solubility indicates that very little barium sulfate actually ionizes. </p><p><b>What experimental techniques can be utilized in order to verify the solubility of BaSO4?</b></p><p>Experimental observations play a crucial role in confirming the insolubility of barium sulfate. Several methods and techniques are employed to assess the solubility of a compound, and in the case of barium sulfate, the following experimental observations contribute to our understanding of its insolubility:</p><ol><li>Precipitation Reaction: One common method to demonstrate the limited solubility of barium sulfate is through a precipitation reaction. When a soluble barium salt (e.g., barium chloride, BaCl₂) is added to a solution containing a soluble sulfate salt (e.g., sodium sulfate, Na₂SO₄), a white precipitate of barium sulfate forms. The appearance of the precipitate indicates that the compound is not fully dissolving in the solution, supporting its insoluble nature.</li></ol><p>BaCl₂(aq) + Na₂SO₄(aq) → BaSO₄(s) + 2NaCl(aq)</p><ol start="2"><li><p>Gravimetric Analysis: Gravimetric analysis is a quantitative method used to determine the concentration of a particular species in a solution by measuring its mass. In the case of barium sulfate, after precipitating the compound as mentioned above, the collected precipitate is filtered, washed, and dried to remove any remaining soluble impurities. The mass of the resulting dried barium sulfate is then measured, and from the stoichiometry of the reaction, the concentration of dissolved barium ions can be calculated. The extremely small mass of barium sulfate obtained in these experiments is indicative of its low solubility.</p></li><li><p>Solubility Curves: A solubility curve represents the relationship between temperature and the solubility of a compound. For barium sulfate, a solubility curve can be constructed by determining the concentration of dissolved barium ions at various temperatures. The resulting curve shows that the solubility of barium sulfate is virtually constant over a wide temperature range, consistent with its insoluble nature.</p></li><li><p>Saturation Point: By adding barium sulfate to water and continuously stirring the mixture, a saturation point is eventually reached where no more solid will dissolve, and any additional barium sulfate added will not disappear into the solution. This point is critical as it shows the maximum concentration of dissolved barium ions that can be achieved, providing further evidence of the compound's limited solubility.</p></li></ol><p>Together, these experimental observations provide strong evidence for the insolubility of barium sulfate in water and support the theoretical understanding derived from the thermodynamics and solubility product constant (K_sp) considerations. The combination of theoretical principles and experimental data reinforces our confidence in the knowledge that barium sulfate is indeed highly insoluble in aqueous solutions.</p><p><b>What are the other properties of BaSO4?</b></p><div class="flex flex-grow flex-col gap-3"><div class="min-h-[20px] flex items-start overflow-x-auto whitespace-pre-wrap break-words flex-col gap-4"><div class="markdown prose w-full break-words dark:prose-invert light"><p>Barium sulfate (BaSO₄) possesses several noteworthy properties, some of which are outlined below:</p><ol><li><p>Physical State: Barium sulfate is a white, crystalline solid at room temperature. It occurs naturally as the mineral "barite" and is commonly synthesized for various applications.</p></li><li><p>Density: Barium sulfate has a relatively high density, typically around 4.5 grams per cubic centimeter (g/cm³). This density makes it useful for certain applications, such as in radiology as a contrast agent.</p></li><li><p>Insolubility: As previously discussed, barium sulfate is highly insoluble in water and most common solvents. This property contributes to its use in medical imaging procedures (e.g., barium sulfate suspensions for X-ray examinations of the gastrointestinal tract) and as a filler in various materials.</p></li><li><p>Chemical Inertness: Barium sulfate is chemically inert, meaning it does not readily react with other substances under normal conditions. This inertness is advantageous in applications where chemical stability is essential, such as in paints, coatings, and plastics.</p></li><li><p>Non-Toxicity: Barium sulfate is considered non-toxic, which further supports its use in medical applications. When consumed in small quantities (e.g., in medical tests), it passes through the body without being absorbed or causing harm.</p></li><li><p>Refractive Index: Barium sulfate has a relatively high refractive index, making it useful as a filler in products like paint and plastics to enhance opacity and brightness.</p></li><li><p>Thermal Stability: Barium sulfate exhibits good thermal stability, retaining its physical and chemical properties at elevated temperatures. This characteristic makes it suitable for applications in industries where high temperatures are involved.</p></li><li><p>Electrical Insulator: Due to its non-conductive nature, barium sulfate serves as an excellent electrical insulator. This property is valuable in applications where electrical isolation is necessary, such as in electronic devices and insulating materials.</p></li><li><p>X-ray Absorption: Barium sulfate has high X-ray absorption properties, which is why it is used as a contrast agent in medical imaging procedures like barium X-rays. It allows for clear visualization of the gastrointestinal tract and certain anatomical structures.</p></li><li><p>Photographic Uses: Barium sulfate was historically used in black-and-white photography as a white pigment in photographic paper and certain emulsions.</p></li></ol><p>Overall, the unique combination of properties exhibited by barium sulfate makes it valuable in various industrial, medical, and commercial applications. Its insolubility, chemical inertness, and X-ray absorption properties, in particular, make it a versatile and sought-after material in different fields.</p></div></div></div>MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com2tag:blogger.com,1999:blog-4138102295975819610.post-17290986025510528712021-03-18T18:03:00.001-07:002021-03-18T18:03:44.306-07:00Is H2S Polar or Nonpolar?<span style="font-size: large;">Answer: H2S is a polar molecule due to the presence of lone pair electrons at the top of the molecule causing a region of partial negative charge due to electron-electron repulsion. </span><br />
<br />H2S has a very similar structure as H2O (see the <a href="https://www.makethebrainhappy.com/2018/01/lewis-dot-structure-for-h2o.html">lewis dot structure for H2O</a> and the <a href="https://www.makethebrainhappy.com/2020/02/is-h2o-polar-or-nonpolar.html">polar/nonpolar explanation</a> at the linked addresses). However, due to the larger size of the sulfur atom compared to oxygen, the bond angle (i.e. the smaller angle between the two hydrogen atoms) is only 92˚ compared to 107.5˚ for H2O. Sulfur contains many more electrons which ultimately due to electron-electron repulsion require a lot more space. Nevertheless the decreased electronegativity of sulfur when compared to hydrogen (2.58 vs. 2.20, respectively) means that the molecule is much less polar overall when compared to H2O. This means that it has a much lower melting and boiling point at -82˚C and -60˚C, respectively. Like <a href="https://www.makethebrainhappy.com/2020/05/is-so2-polar-or-nonpolar.html">SO2</a> the presence of sulfur means that this molecule has a pungent odor in gaseous form although it is colorless. <br /><br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-JllqF7ibu8Y/XpEw_h2-4FI/AAAAAAAAB74/TRkxo99AuvIR3MgMyPjPkskAjjuMXJ6qQCLcBGAsYHQ/s1600/H2SBallAndStickDiagram.webp" style="margin-left: auto; margin-right: auto;"><img alt="H2S Ball and Stick Diagram" border="0" data-original-height="704" data-original-width="1056" height="426" src="https://1.bp.blogspot.com/-JllqF7ibu8Y/XpEw_h2-4FI/AAAAAAAAB74/TRkxo99AuvIR3MgMyPjPkskAjjuMXJ6qQCLcBGAsYHQ/s640/H2SBallAndStickDiagram.webp" title="H2S Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">H2S Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=402">MolView</a>.</td></tr>
</tbody></table>
<br /><div><b>How is H2S utilized in the real world?</b></div><div><br /></div><div>Hydrogen sulfide appears in many different ways within the natural world. For starters it is an important constituent of the sulfur cycle. Bacteria oftentimes convert the sulfur from organic elements to inorganic molecules such as H2S. The main use of hydrogen sulfide is as a storage compound which can be converted to pure sulfur during reactions to form all kinds of sulfur-containing compounds. Hydrogen sulfide may have also caused a mass extinction due to its buildup within the atmosphere. Based on this fact it is not difficult to imagine the toxicity of hydrogen sulfide towards life forms such as human beings. It negatively impacts proper nervous system functioning primarily although it will affect other body systems as well. Nevertheless there are certain organisms adapted to live in high-H2S conditions due to those environments existing in deep underwater volcanic sea vents. </div>MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com8tag:blogger.com,1999:blog-4138102295975819610.post-2315878912924065312021-02-24T15:23:00.022-08:002021-02-24T15:27:17.508-08:00The Lewis Dot Structure for Acetic Acid (CH3COOH)<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto;"><tbody><tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-bj5_wDf5REg/YDbgRrLLWCI/AAAAAAAACNg/IK27PE_3JXsvCm6Qydn2NzBO8V8FWJUCgCPcBGAYYCw/s777/Lewis%2BStructure%2Bfor%2BAcetic%2BAcid.png" imageanchor="1" style="margin-left: auto; margin-right: auto; text-align: center;"><img alt="Lewis Dot Structure for Acetic Acid" border="0" data-original-height="485" data-original-width="777" height="400" src="https://1.bp.blogspot.com/-bj5_wDf5REg/YDbgRrLLWCI/AAAAAAAACNg/IK27PE_3JXsvCm6Qydn2NzBO8V8FWJUCgCPcBGAYYCw/w640-h400/Lewis%2BStructure%2Bfor%2BAcetic%2BAcid.png" title="Lewis Dot Structure for Acetic Acid" width="640" /></a></td></tr><tr><td class="tr-caption" style="text-align: center;">Created by MakeTheBrainHappy.</td></tr></tbody></table><div><br /><div>
Above is the Lewis Dot Structure for Acetic Acid (CH3COOH). You could alternatively also draw the structure by including two dots for every bond. As you can see every single element has a filled valence shell with the two oxygen's each containing two lone pairs of electrons, the only instance of this phenomena within the Lewis Structure. In a sense this is a modified <a href="https://www.makethebrainhappy.com/2018/03/the-lewis-dot-structure-for-ch4.html">structure of methane (CH4)</a> with the replacement of one hydrogen with the replacement of a carboxylic group (-COOH). As we will see the properties we observe within the Lewis structure have a significant impact on the properties of acetic acid.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-pvTSWktd5Gk/XuQnsjuocHI/AAAAAAAACHA/bvN93xkf_Ak5GAdytC_RuqRD53a40ulugCLcBGAsYHQ/s1600/Teofrasto_Orto_botanico_detail.webp" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="1200" data-original-width="900" height="320" src="https://1.bp.blogspot.com/-pvTSWktd5Gk/XuQnsjuocHI/AAAAAAAACHA/bvN93xkf_Ak5GAdytC_RuqRD53a40ulugCLcBGAsYHQ/s320/Teofrasto_Orto_botanico_detail.webp" width="240" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">The Greek Philosopher Theophrastus. <a href="https://commons.wikimedia.org/wiki/File:Teofrasto_Orto_botanico_detail.jpg">Source</a></td></tr>
</tbody></table><br /></div><div><b>
What is the history of acetic acid?<br /></b>
<br />
Due to the importance of different alcohols such as beer and wine in early civilizations, vinegar became one of the earliest chemical substances that was familiar to ancient peoples. Vinegar is formed by natural fermentation processes and contains approximately 5% acetic acid. One of the earliest mentions of acetic acid was by the <span style="text-align: center;">Greek Philosopher Theophrastus who explained how to form different pigments, including those for white and green colors, with vinegar as an important constituent ingredient. </span><br />
<br /><b>
Is Acetic Acid (CH3COOH) Polar or Nonpolar?</b></div><div><br /></div><div>Acetic Acid (CH3COOH) is a polar molecule due to the presence of the functional group COOH, a carboxylic acid. It is also an acid in solution, releasing a small number of protons into solution which form H3O+. Due to its polar qualities it is found as a liquid at standard temperature and pressure in relation to its rather light molar mass. It has a melting point is between 16˚C to 17˚C while the boiling point is between 118˚C and 119˚C. These are again elevated due to the polarity of acetic acid. </div><div><br /></div><div><b>How is Acetic Acid (CH3COOH) utilized in the real world?</b></div><div><br /></div><div>Acetic acid is useful due to its properties as a polar solvent and building block for other molecules, containing both a methyl (CH3) and COOH functional group. Nearly one third of produced acetic acid is utilized in order to produce "Elmer's glue" material. Inks, paints and coatings are also created via a reaction involving acetic acid. It is frequently utilized as a polar solvent in lab research settings and thereby has been involved in certain medical practices. As mentioned above acetic acid is also present in vinegar which has a variety of household uses; however, the acetic acid is diluted in water to a greater degree than in a research lab. </div><div>
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<br /></div><br /><div class="separator" style="clear: both; text-align: center;"><br /></div><br /></div>MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com5tag:blogger.com,1999:blog-4138102295975819610.post-69963629298634337392020-10-20T14:22:00.006-07:002020-10-20T14:24:32.379-07:00Downloading FASTQ Files Quickly utilizing IBM’s Aspera Connect on a LINUX or MAC Machine<div class="separator" style="clear: both; text-align: center;"><a href="https://1.bp.blogspot.com/-exC767AuuG4/X49UYaJ1ZoI/AAAAAAAACJI/Y8wwPeOhXPwVnaDz1qnddkc5SHcEDuYxwCLcBGAsYHQ/s297/VersionScreenshot.png" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="227" data-original-width="297" src="https://1.bp.blogspot.com/-exC767AuuG4/X49UYaJ1ZoI/AAAAAAAACJI/Y8wwPeOhXPwVnaDz1qnddkc5SHcEDuYxwCLcBGAsYHQ/s0/VersionScreenshot.png" /></a></div><p><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 10pt; font-style: italic; font-variant-east-asian: normal; font-variant-numeric: normal; text-align: center; vertical-align: baseline; white-space: pre-wrap;">Please note that this guide is based on this </span><a href="https://www.biostars.org/p/325010/" style="text-align: center; text-decoration-line: none;"><span face="Montserrat, sans-serif" style="color: #1155cc; font-size: 10pt; font-style: italic; font-variant-east-asian: normal; font-variant-numeric: normal; text-decoration-line: underline; text-decoration-skip-ink: none; vertical-align: baseline; white-space: pre-wrap;">BioStars thread</span></a><span face="Montserrat, sans-serif" style="font-size: 10pt; font-style: italic; font-variant-east-asian: normal; font-variant-numeric: normal; text-align: center; vertical-align: baseline; white-space: pre-wrap;"> and this </span><a href="https://github.com/wwood/ena-fast-download" style="text-align: center; text-decoration-line: none;"><span face="Montserrat, sans-serif" style="color: #1155cc; font-size: 10pt; font-style: italic; font-variant-east-asian: normal; font-variant-numeric: normal; text-decoration-line: underline; text-decoration-skip-ink: none; vertical-align: baseline; white-space: pre-wrap;">GitHub repository</span></a><span face="Montserrat, sans-serif" style="font-size: 10pt; font-style: italic; font-variant-east-asian: normal; font-variant-numeric: normal; text-align: center; vertical-align: baseline; white-space: pre-wrap;">. </span></span></p><span style="font-family: inherit;"><br /></span><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span face="Montserrat, sans-serif" style="font-family: inherit; font-size: 12pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">Procedure:</span></p><span style="font-family: inherit;"><br /></span><ol style="margin-bottom: 0px; margin-top: 0px;"><li dir="ltr" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; list-style-type: decimal; vertical-align: baseline; white-space: pre;"><p dir="ltr" role="presentation" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">Download the latest version of </span><a href="https://www.ibm.com/products/aspera/downloads?list" style="text-decoration-line: none;"><span style="color: #1155cc; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; text-decoration-line: underline; text-decoration-skip-ink: none; vertical-align: baseline; white-space: pre-wrap;">Aspera Connect</span></a><span style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> from the IBM “featured client software” section (you may need to install a browser extension as well)</span></span></p></li></ol><span style="font-family: inherit;"><br /></span><ol start="2" style="margin-bottom: 0px; margin-top: 0px;"><li dir="ltr" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; list-style-type: decimal; vertical-align: baseline; white-space: pre;"><p dir="ltr" role="presentation" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">Download the file “ena-fast-download.py” from wwood’s </span><a href="https://github.com/wwood/ena-fast-download" style="text-decoration-line: none;"><span style="color: #1155cc; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; text-decoration-line: underline; text-decoration-skip-ink: none; vertical-align: baseline; white-space: pre-wrap;">GitHub repository</span></a></span></p></li></ol><span style="font-family: inherit;"><br /></span><ol start="3" style="margin-bottom: 0px; margin-top: 0px;"><li dir="ltr" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; list-style-type: decimal; vertical-align: baseline; white-space: pre;"><p dir="ltr" role="presentation" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">Open the script in your favorite python editor and scroll down to the bottom. Add the specific file path to the ascp field (addition highlighted below)</span></p></li></ol><span style="font-family: inherit;"><br /></span><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span face="Montserrat, sans-serif" style="font-family: inherit; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">aspera_commands = []</span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">for url in ftp_urls:</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">quiet_args = ''</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">if args.quiet:</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">quiet_args = ' -Q'</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">cmd = "</span><span face="Montserrat, sans-serif" style="background-color: #bf9000; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">/Users/USER/Applications/Aspera\ Connect.app/Contents/Resources/</span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">ascp{} -T -l 300m -P33001 {} -i {} era-fasp@fasp.sra.ebi.ac.uk:{} {}".format(</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">quiet_args,</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">args.ascp_args,</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">ssh_key_file,</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">url.replace('ftp.sra.ebi.ac.uk',''), output_directory)</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">logging.info("Running command: {}".format(cmd))</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> </span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">subprocess.check_call(cmd,shell=True)</span></span></p><span style="font-family: inherit;"><br /></span><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span face="Montserrat, sans-serif" style="font-family: inherit; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">logging.info("All done.") </span></p><span style="font-family: inherit;"><br /></span><ol start="4" style="margin-bottom: 0px; margin-top: 0px;"><li dir="ltr" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; list-style-type: decimal; vertical-align: baseline; white-space: pre;"><p dir="ltr" role="presentation" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">Save the file. Move the file to the directory where you want FASTQ files to be deposited into. Run the following command in terminal for each accession number (example highlighted):</span></p></li></ol><span style="font-family: inherit;"><br /></span><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">./ena-fast-download.py </span><span face="Montserrat, sans-serif" style="background-color: #bf9000; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">ERR1739691</span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> --ssh_key osx </span></span></p><span style="font-family: inherit;"><br /></span><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span style="font-family: inherit;"><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">Note: Sequential commands can be done through a looped text file call or with the ; operator (ex. ./ena-fast-download.py </span><span face="Montserrat, sans-serif" style="background-color: #bf9000; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">key1</span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> --ssh_key osx ; /ena-fast-download.py </span><span face="Montserrat, sans-serif" style="background-color: #bf9000; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">key2</span><span face="Montserrat, sans-serif" style="font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"> --ssh_key osx)</span></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span face="Montserrat, sans-serif" style="font-family: inherit; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;"><br /></span></p><p dir="ltr" style="line-height: 1.38; margin-bottom: 0pt; margin-top: 0pt;"><span face="Montserrat, sans-serif" style="font-family: inherit; font-size: 11pt; font-variant-east-asian: normal; font-variant-numeric: normal; vertical-align: baseline; white-space: pre-wrap;">Note 2: For this method it is recommended that you utilize a bash terminal. </span></p>MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com5tag:blogger.com,1999:blog-4138102295975819610.post-69466173735019966792020-06-14T08:22:00.000-07:002020-06-14T08:22:01.977-07:00The Lewis Dot Structure for KCl<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-KIRVvjPBugo/XuY72EksgdI/AAAAAAAACHM/uf_1Px0PvsIbDJnlktn6bfDzVAclOTIXwCLcBGAsYHQ/s1600/Lewis%2BStructure%2Bfor%2BKCl.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Lewis Dot Structure for KCl" border="0" data-original-height="404" data-original-width="960" height="268" src="https://1.bp.blogspot.com/-KIRVvjPBugo/XuY72EksgdI/AAAAAAAACHM/uf_1Px0PvsIbDJnlktn6bfDzVAclOTIXwCLcBGAsYHQ/s640/Lewis%2BStructure%2Bfor%2BKCl.webp" title="Lewis Dot Structure for KCl" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Created by MakeTheBrainHappy.</td></tr>
</tbody></table>
Please find above the Lewis Dot Structure for KCl (Potassium Chloride). As per usual you could replace the one bond with two electrons. In the case for KCl the electronegativity difference between potassium and chloride is so strong (.82 vs. 3.16, respectively) that the bond is considered ionic. The electrons aren't really considered "shared"; rather, the valence electrons are nearly completely coopted by the chloride. This property as illustrated by the Lewis Dot Structure gives KCl many of its properties as will be explored in the following paragraphs.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-omE8SzFo4CI/XuY9mD7HkUI/AAAAAAAACHY/a-GvwMuCNzA4vgM8O_3UM6f2DT4uvYb5gCLcBGAsYHQ/s1600/KClDissolving%2B.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="KCl Dissolving in Water." border="0" data-original-height="851" data-original-width="975" height="556" src="https://1.bp.blogspot.com/-omE8SzFo4CI/XuY9mD7HkUI/AAAAAAAACHY/a-GvwMuCNzA4vgM8O_3UM6f2DT4uvYb5gCLcBGAsYHQ/s640/KClDissolving%2B.webp" title="KCl Dissolving in Water." width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">KCl Dissolving in Water. <a href="https://socratic.org/questions/56b6d3e911ef6b539110b448">Source</a></td></tr>
</tbody></table>
<b>How does KCl (potassium chloride) act as a solute?</b><br />
<br />
As a result of its ionic character as shown in the Lewis Dot Structure it has a great partial positive and partial negative charge on either end. Therefore it dissolves very well in polar solvents such as water (shown above). Water molecules essentially surround the different individual ions and thereby disassociate the salt into solution. However since you need many water molecules per ion there can be a point where you saturate the solution. This means that no more salt can be disassociated unless you add more of the polar solvent.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-2tHanzE9fTY/XuY-B1sGEzI/AAAAAAAACHg/KOAx1iSQke8puuY4ZQBSNbnYOYmzzIpswCLcBGAsYHQ/s1600/KClMolecule.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="KCl Ball and Stick Structure" border="0" data-original-height="566" data-original-width="1410" height="256" src="https://1.bp.blogspot.com/-2tHanzE9fTY/XuY-B1sGEzI/AAAAAAAACHg/KOAx1iSQke8puuY4ZQBSNbnYOYmzzIpswCLcBGAsYHQ/s640/KClMolecule.webp" title="KCl Ball and Stick Structure" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">KCl Molecule. Created with <a href="http://molview.org/?cid=4873">MolView</a>.</td></tr>
</tbody></table>
<b>Is KCl (potassium chloride) polar or nonpolar?</b><br />
<br />
As you may have guessed from the above paragraph, KCl is a polar molecule due to the great electronegativity difference discussed before. This incredibly large difference means that the compound is a solid at standard pressure and temperature with a melting point of 770˚C and a boiling point of 1420˚C. The act of disassociation as mentioned above is not equivalent to melting the pure compound into a liquid as we are discussing here. These properties are also presupposed in the Lewis Dot Structure for KCl.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-OoxSysbkDKc/XuY_XRM33uI/AAAAAAAACHs/8bPKiTjtl9o4wMSC--nT23hRDc-qSMBxQCLcBGAsYHQ/s1600/KClSalt.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="KCl Salt" border="0" data-original-height="501" data-original-width="566" height="564" src="https://1.bp.blogspot.com/-OoxSysbkDKc/XuY_XRM33uI/AAAAAAAACHs/8bPKiTjtl9o4wMSC--nT23hRDc-qSMBxQCLcBGAsYHQ/s640/KClSalt.webp" title="KCl Salt" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">KCl Salt. <a href="https://www.aliexpress.com/item/32495601962.html">Source</a></td></tr>
</tbody></table>
<b>How is KCl (potassium chloride) utilized in the real world?</b><br />
<br />
There are a wide variety of uses for potassium chloride. There are different fertilizers which are composed of KCl for usage in agriculture. Due to the necessity of potassium in biological systems the salt form shown above is often consumed by those who are potassium-deficient. In regular food it can be utilized as a table salt (NaCl) substitute in order to lower the actual Na+ salt content in someones diet. Lastly it is found in many different niche industrial uses as a "ice" salt or in the creation of potassium metal for example. In conclusion, the different properties that allow for these utilizations are exemplified by the Lewis Dot Structure for KCl.MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com4tag:blogger.com,1999:blog-4138102295975819610.post-16937309849503633432020-06-11T12:27:00.000-07:002020-06-11T12:27:44.308-07:00The Lewis Dot Structure for CS2 <table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-MHzPqwS9-8I/XuJq41zdosI/AAAAAAAACGk/ILgXai3-oNMZfavIBFnwuK94I5XKG8UQACLcBGAsYHQ/s1600/Lewis%2BStructure%2Bfor%2BCS2%2B%25281%2529.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="CS2 Lewis Dot Structure" border="0" data-original-height="404" data-original-width="960" height="268" src="https://1.bp.blogspot.com/-MHzPqwS9-8I/XuJq41zdosI/AAAAAAAACGk/ILgXai3-oNMZfavIBFnwuK94I5XKG8UQACLcBGAsYHQ/s640/Lewis%2BStructure%2Bfor%2BCS2%2B%25281%2529.webp" title="CS2 Lewis Dot Structure" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">CS2 Lewis Structure. Created by MakeTheBrainHappy</td></tr>
</tbody></table>
This is the Lewis Dot Structure for Carbon Disulfide (CS2). As we've discussed before you could replace each bond with two electrons which would represent well how through the sharing of electrons each atom achieves a full octet. The combination of four electrons for the bonds and four electrons in lone pairs equals eight for sulfur while bonds supply eight electrons for the central carbon atom. This is a common feature for carbon as it is unlikely for this element in particular to have lone pair electrons.<br />
<br />
The lewis dot structure for CS2 also predicts many of the properties of the molecule. Due to the presence of large sulfide atoms over for <a href="https://www.makethebrainhappy.com/2018/01/lewis-dot-structure-for-co2.html">comparison oxygen atoms in CO2</a> the molecule has a greater capacity for temporary london dispersion forces. As a result there can be more induced dipoles which increases the solubility of CS2. The compound is slightly soluble within water and much more soluble in less polar compounds such as alcohol or even nonpolar compounds like <a href="https://www.makethebrainhappy.com/2020/03/is-benzene-polar-or-nonpolar.html">benzene</a>.<br />
<div>
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-DjGcHyq1h6U/XuJqJ5m8omI/AAAAAAAACGg/kfHJ4SqHZosuunzRkVMiGoWsXsXeMFQngCLcBGAsYHQ/s1600/maxresdefault%2B%25281%2529.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="CS2 Liquid State" border="0" data-original-height="720" data-original-width="1280" height="360" src="https://1.bp.blogspot.com/-DjGcHyq1h6U/XuJqJ5m8omI/AAAAAAAACGg/kfHJ4SqHZosuunzRkVMiGoWsXsXeMFQngCLcBGAsYHQ/s640/maxresdefault%2B%25281%2529.webp" title="CS2 Liquid State" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">CS2 Liquid State. <a href="https://www.youtube.com/watch?v=UrUqPIFep1s">Source</a></td></tr>
</tbody></table>
<b>How is CS2 utilized in the real world?</b><br />
<br />
Due to the stronger induced dipoles CS2 also has a greater melting and boiling point. This means that the compound is a liquid at standard temperature and pressure. This concept is discussed further in our article on the polarity of CS2 which you can learn more about in the next section. There are only a limited number of uses for CS2 due to its pretty toxic properties. One of these uses is as a solvent for other nonpolar compounds. These include many elements like phosphorus and sulfur and also larger compounds like fats, resins and rubber. There also other uses for different chemical reactions involved in metallurgy and rubber production. One of the most popular reactions involving CS2 produces carbon tetrachloride (CCl4).<br />
<br />
<b>Is CS2 polar or nonpolar?</b><br />
<br />
If you are interested in learning more about this subject, feel free to <a href="https://www.makethebrainhappy.com/2020/02/is-cs2-polar-or-nonpolar.html">read this article on whether CS2 is polar or nonpolar</a>. The article will also discuss some of the ways in which CS2 differs from CO2. In addition it will also go into the underlying reasons behind the determination of CS2s polarity.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-aS076Yaitpc/XuJsPqZxL4I/AAAAAAAACG0/3KTP_KCdjg4-v7eGWUvo75GkZrsONGvWwCLcBGAsYHQ/s1600/1572046220785.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Volcanic Eruption" border="0" data-original-height="744" data-original-width="992" height="480" src="https://1.bp.blogspot.com/-aS076Yaitpc/XuJsPqZxL4I/AAAAAAAACG0/3KTP_KCdjg4-v7eGWUvo75GkZrsONGvWwCLcBGAsYHQ/s640/1572046220785.webp" title="Volcanic Eruption" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Volcanic eruption. <a href="https://www.arcgis.com/sharing/rest/content/items/a07a68d9c95d4fcdb163b4d18104bac7/resources/1572046220785.jpeg?w=1600">Source</a></td></tr>
</tbody></table>
<b>How can CS2 be formed naturally?</b><br />
<br />
CS2 (carbon disulfide) can be formed naturally by volcanic eruptions or in marshes. The way this reaction occurs is actually very compatible with how you can see the molecule within the Lewis Dot Structure. Elemental carbon and sulfide combine at very high temperatures to form CS2. However, it should be noted that there is only a very small amount of the compound formed in this process. </div>
MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com2tag:blogger.com,1999:blog-4138102295975819610.post-8642145793301233382020-05-28T18:16:00.001-07:002020-05-30T19:02:32.373-07:00Biography of J. Isfred Isidore Hofbauer (J. Hofbauer)<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-zlg3SzSgNso/Xs_C3h5tH0I/AAAAAAAACCE/_GPSRvkHQHYp8LyGZBEwEPHJxJVmMKMKACLcBGAsYHQ/s1600/JHofbauerPhoto.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="J. Isfred Isidore Hofbauer Portrait" border="0" data-original-height="710" data-original-width="560" height="320" src="https://1.bp.blogspot.com/-zlg3SzSgNso/Xs_C3h5tH0I/AAAAAAAACCE/_GPSRvkHQHYp8LyGZBEwEPHJxJVmMKMKACLcBGAsYHQ/s320/JHofbauerPhoto.webp" title="J. Isfred Isidore Hofbauer Portrait" width="252" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">undated photo of J. Hofbauer [1]</td></tr>
</tbody></table>
<br />
J. (Jsidro) Isfred Isidore Hofbauer or simply <b>J. Hofbauer </b>(born <a href="https://www.findagrave.com/memorial/153367876/isfred-i_-hofbauer">September 8th, 1871</a> in Vienna, Austria - March 13th, 1961 in Cincinnati, US) was a Austrian-born American gynecologist who performed extensive studies of obstetric organ systems and pioneered new treatments with regard to childbirth. Furthermore, he doubled as an oncologist formulating early operations to treat breast cancer. [2]<br />
<br />
<b>Early Life</b><br />
<br />
Hofbauer was of Scandinavian and Austrian heritage. [3] His parents were Moritz Hofbauer and Jeanette Gewitsch. [4]<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-zFy0HkyqB8g/Xs_a_JI30NI/AAAAAAAACCQ/kyUXKBEy6GEzjZ9Miyh3MAKIyPTYz08FQCLcBGAsYHQ/s1600/JohnsHopkinsWomensClinic.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="John's Hopkins Medical School Women's Clinic - circa 1924" border="0" data-original-height="671" data-original-width="800" height="536" src="https://1.bp.blogspot.com/-zFy0HkyqB8g/Xs_a_JI30NI/AAAAAAAACCQ/kyUXKBEy6GEzjZ9Miyh3MAKIyPTYz08FQCLcBGAsYHQ/s640/JohnsHopkinsWomensClinic.webp" title="John's Hopkins Medical School Women's Clinic - circa 1924" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Johns Hopkins Hospital Women's Clinic circa 1924. [5]</td></tr>
</tbody></table>
<b><br /></b>
<b>University Associations</b><br />
<br />
He studied at medicine at the University of Vienna. He did his residency at the Nothnagel Clinic and the Women's Clinic at the Bettina Pavilion. He studied under Friedrich Shauta and Ernst Wertheim for his postgraduate work. He was the lead doctor in the Women's Clinic at Königsberg University from between 1906 and 1912. In 1909 he became the chair of gynecology and obstetrics at the University of Königsberg. He was invited in 1924 by John Whitridge Williams to join the faculty of Johns Hopkins University, where he served as an Associate Professor. In 1933 he moved to the University of Cincinnati where he continued to be an Associate Professor of Obstetrics and gynecologist at the Jewish and Good Samaritan Hospitals. [2,3,4]<br />
<br />
<b>Scientific Career</b><br />
<br />
In 1896, J. Hofbauer proposed a "neuclein" treatment for severe infections about childbirth, providing a positive assessment as to its potential due to positive results in seven patients. [6] He continued to experiment with this treatment, continuing to report positive while others in the field attempted to extend the field to inoculation from disease as well. [7] Hofbauer was known to emphasize the techniques efficiency when delivered via the stomach. [7] At the time the "neuclein" was defined to be the part of blood serum left over after digestion within the stomach. [8] Although it was theorized that special "white blood cells" within the blood with phagocytic properties were responsible for the remedy for bacterial infection, this was only one of a few competing theories. [8] The injection of serum was typically accompanied by a saline solution injection and occasionally damaged the bone marrow of the patients [9]. Studies by other researchers to "inoculate" for specific bacteria with blood serum injections were unsuccessful [7].<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-gQPDIrCie88/Xs_vfXSA8LI/AAAAAAAACCc/0xZOhPaagkw4oFMzdEIJ_EYg_1UreN1SwCLcBGAsYHQ/s1600/HofbauerBookCoverPage.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="J. Hofbauer - Biology of the Human Placenta Cover Page" border="0" data-original-height="1074" data-original-width="1600" height="428" src="https://1.bp.blogspot.com/-gQPDIrCie88/Xs_vfXSA8LI/AAAAAAAACCc/0xZOhPaagkw4oFMzdEIJ_EYg_1UreN1SwCLcBGAsYHQ/s640/HofbauerBookCoverPage.webp" title="J. Hofbauer - Biology of the Human Placenta Cover Page" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Translation: Biology of the Human Placenta with a special emphasis on the question of fetal nourishment by Dr. J. Hofbauer</td></tr>
</tbody></table>
<br />
J. Hofbauer published a book in 1905 regarding a morphological study he conducted of the human placenta. [10] He described visible "fat cells" within the developing fetus. [11] There was also a special kind of "vacuolated" cell that he described in great detail within the book.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-AHxZMsV6yHs/Xs_zo3cG15I/AAAAAAAACCo/dJYljimObS8s_OaHGplE3B6zodVJWqIGgCLcBGAsYHQ/s1600/vacuolatedCellHofbauer.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="200" data-original-width="416" height="153" src="https://1.bp.blogspot.com/-AHxZMsV6yHs/Xs_zo3cG15I/AAAAAAAACCo/dJYljimObS8s_OaHGplE3B6zodVJWqIGgCLcBGAsYHQ/s320/vacuolatedCellHofbauer.webp" width="320" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">"Vacuolated" cells within the first Table in Appendix of J. Hofbauer's book.</td></tr>
</tbody></table>
<br />
In his 1925 paper entitled "THE FUNCTION OF THE HOFBAUER CELLS OF THE CHORIONIC VILLUS PARTICULARLY IN RELATION TO ACUTE INFECTION AND SYPHILIS" [12], J. Hofbauer translated his original description of the cells which would later become known as Hofbauer cells:<br />
<blockquote class="tr_bq">
“These specific cells make their appearance by the end of the fourth week of pregnancy. They are comparatively abundant in the early stages of the placenta and decrease in number later on, as the connective tissue of the villus gradually assumes a more fibrous character. The duration of life of the individual cells is shown by the fact that they vanish after total vacuolization. In the cytoplasm which primarily contains homogenous or delicate granules, minute pellucid spots gradually appear about the periphery of the nucleus; later increase in size, and form a clear area surrounding it. These spaces which are filled with fluid and are separated from one another by thin septa, may fuse together, and thus give rise to larger vacuoles. Similar foam-like structures subsequently occur in the peripheral zone of the cells, as well. Furthermore, an essential part of the cytoplasm is represented by smaller and larger granules. In the beginning, these cells are intimately connected with the stroma cells of the villi and are to be considered as descendants of the original mesenchyme. Marchand holds the same view. Staining fresh placental tissue with neutral red throws the vacuolated cells into the boldest relief, while the surrounding tissue remains unstained. It is the granules and the vacuoles of the cells which take up the dye with avidity. These are the fundamental structural constituents of the cells in question, and they may play a considerable biologic part. As to their physiologic role, we can only say that they probably possess a digestive function,--a view which is supported by the presence of fat in the vacuoles, as well as of neutral red. The phagocytic power is further supported by the fact that at the stage of development, when the nucleated red blood cells lose their nuclei, I could demonstrate the disintegration of their nuclei within the fetal capillaries of the chorionic villi, and that the fragments of the nuclei were engulfed by the cytoplasm of a type of cells quite comparable in structure to our vacuolated cells. As this phenomenon could be observed distinctly in various specimens, it became obvious that our cells may bc regarded as wandering cells, which had gained access to the fetal blood stream, and thereby constituted a portion of its white cells.” </blockquote>
He also included a clearer figure with stained Hofbauer cells (HBCs) exclusively within his 1925 paper, which then goes on the delineate rapid increase in the number of HBCs in response acute infection. These kinds of morphological studies were common within Hofbauer's research. This indicates that the Hofbauer cells were being seriously considered to be macrophages as early as 1924/1925. [12]<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-mGZBwNqXHiY/Xs_3_C9_HpI/AAAAAAAACC0/q8tz-nNoSaAFdsAJ24nNVG3ajU_v0oNqACLcBGAsYHQ/s1600/HofbauerCells1925.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Hofbauer Cells - 1925" border="0" data-original-height="782" data-original-width="1230" height="406" src="https://1.bp.blogspot.com/-mGZBwNqXHiY/Xs_3_C9_HpI/AAAAAAAACC0/q8tz-nNoSaAFdsAJ24nNVG3ajU_v0oNqACLcBGAsYHQ/s640/HofbauerCells1925.webp" title="Hofbauer Cells - 1925" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Fig. 1: Section through normal villus at third month, showing Hofbauer cells.</td></tr>
</tbody></table>
<br />
Hofbauer also found that these cells reacted in a similar manner to a certain dye as other cells within the bone marrow and Kupffer cells, foreshadowing their future similarities as tissue-resident macrophages. [12]<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-cRtcxyv5j_U/XtBcllVzouI/AAAAAAAACDM/C4YQOaVw26M9p1gobXREwspOyhahSaQ0QCLcBGAsYHQ/s1600/PituitaryExtractHofbauer.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="498" data-original-width="918" height="346" src="https://1.bp.blogspot.com/-cRtcxyv5j_U/XtBcllVzouI/AAAAAAAACDM/C4YQOaVw26M9p1gobXREwspOyhahSaQ0QCLcBGAsYHQ/s640/PituitaryExtractHofbauer.webp" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Advertisement for Pituitary Extract featuring a glowing review by Hofbauer. [13] </td></tr>
</tbody></table>
<br />
He was also one of the first gynecologists to utilize pituitrin, an extraction from cattle pituitary hormones, in order to help deal with labor pains. By the time the advertisement above was published, Hofbauer had applied the treatment to twelve patients and stated that "there were no unfavorable after-effects." [13] He recommended the product for "all forms of primary and secondary uterine inertia," noting that the introduction of these hormones has removed the need for many once common complex surgical procedures. [14] Reflecting in 1955 within his paper, <i>Forty Years of Postpituitary Extract in Obstetrics</i>, Hofbauer wrote the following [15]:<br />
<blockquote class="tr_bq">
THE importance of the initial impulse that a fascinating experimental observation may inspire for its application to spheres of considerable practical interest is forcefully illustrated by the mosaic of significant advances
which resulted from the report by H. H. Dale of vigorous contractions of the
virgin guinea pig's uterus suspended in a neutral solution, induced by the addition of post-pituitary extract. Factual background data form the basis of
the present attempt of an objective evaluation of the merits of post-pituitary
preparations as a therapeutic standby, while an exhaustive review of the subject is not in the scope of this survey. </blockquote>
The reflection above characters much of Hofbauer's research: a kind of try-and-see approach that attempted to find success and justified the original experiments with factual evidence afterwards.<br />
<br />
Hofbauer also attempted to connect the human pituitary gland to the origins of cancer within mothers. He saw the cancer as a continued production of growth hormone that led to increased cell division. Although he was unable to link his theory to all cancers, Hofbauer successfully utilized X-ray radiology on the pituitary to help patients which was a precursor to modern radiation treatments. [16]<br />
<br />
<b>Character</b><br />
<br />
Thomas F. Baskett wrote in his book, <i>Eponyms and Names in Obstetrics and Gynaecology</i>, that Hofbauer was "arrogant, egotistical and aggressive." Baskett recalls a story where Hofbauer told a junior colleague to write about their meeting in this manner: "Go home and write in your diary that today you talked to Hofbauer." [3]<br />
<br />
<b>Supplemental Image</b><br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-Giq_8Y-kLkw/XtEu8czqq7I/AAAAAAAACDY/QWdJ9C9O32UN5nFn1ZJiOJvJWXHBB7PjwCLcBGAsYHQ/s1600/Screen%2BShot%2B2020-05-28%2Bat%2B2.17.16%2BPM.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Stained Placental Cross-Section by Hofbauer" border="0" data-original-height="415" data-original-width="640" height="414" src="https://1.bp.blogspot.com/-Giq_8Y-kLkw/XtEu8czqq7I/AAAAAAAACDY/QWdJ9C9O32UN5nFn1ZJiOJvJWXHBB7PjwCLcBGAsYHQ/s640/Screen%2BShot%2B2020-05-28%2Bat%2B2.17.16%2BPM.webp" title="Stained Placental Cross-Section by Hofbauer" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 12.8px;">Stained Placental Cross-Section by Hofbauer for Iron Absorption (1905)</span></td></tr>
</tbody></table>
<b><br /></b>
<b>References</b><br />
<br />
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
1. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
J. Isfred Isidor Hofbauer, http://hdl.handle.net/2193/5138JF11M.</div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
2. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
Times S to TNY. Dr. Isfred Hofbauer, a Gynecologist, 89. <i>New York Times</i>. 1961:39.</div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
3. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
Baskett TF. <i>Eponyms and Names in Obstetrics and Gynaecology</i>. 3rd ed. Cambridge University Press; 2019. doi:<a href="https://doi.org/10.1017/9781108421706">10.1017/9781108421706</a></div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
4. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
Österreichische Nationalbibliothek, ed. <i>Handbuch Österreichischer Autorinnen Und Autoren Jüdischer Herkunft: 18. Bis 20. Jahrhundert</i>. DE GRUYTER SAUR; 2002. doi:<a href="https://doi.org/10.1515/9783110949001">10.1515/9783110949001</a></div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
5. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
[Johns Hopkins Hospital Woman’s Clinic, circa 1924]. Flickr. Accessed May 28, 2020. <a href="https://www.flickr.com/photos/medical_archives/3570325755/">https://www.flickr.com/photos/medical_archives/3570325755/</a></div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
6. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
Company P Davis &. <i>Nuclein Therapy</i>. Parke, Davis & Company; 1900.</div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
7. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
<i>The Cincinnati Lancet-Clinic</i>. J.C. Culbertson; 1904.</div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
8. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
Ames D. THE NATURE OF THE LEUCOCYTOSIS PRODUCED BY NUCLEINIC ACID; A PRELIMINARY EXPERIMENTAL STUDY. <i>JAMA</i>. 1897;XXIX(10):472. doi:<a href="https://doi.org/10.1001/jama.1897.02440360016002e">10.1001/jama.1897.02440360016002e</a></div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
9. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
<i>The American Journal of Obstetrics and Diseases of Women and Children</i>. W.A. Townsend & Adams; 1903.</div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
10. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
Hofbauer Jsidro. <i>Grundzüge Einer Biologie Der Menschlichen Plazenta, Mit Besonderer Berucksichtigung Fragen Der Fötalen Ernährung</i>. W. Braumüller; 1905. Accessed May 28, 2020. <a href="https://catalog.hathitrust.org/Record/006744605">https://catalog.hathitrust.org/Record/006744605</a></div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
11. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
<i>Archives of Internal Medicine</i>. American Medical Association.; 1923.</div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
12. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
Hofbauer
J. The function of the hofbauer cells of the chorionic villus
particularly in relation to acute infection and syphilis. <i>American Journal of Obstetrics and Gynecology</i>. 1925;10(1):1-14. doi:<a href="https://doi.org/10.1016/S0002-9378(25)90514-5">10.1016/S0002-9378(25)90514-5</a></div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
13. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
<i>The Journal of the Arkansas Medical Society</i>. Arkansas Medical Society.; 1912.</div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
14. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
<i>Therapeutic Notes</i>. Parke, Davis & Company; 1912.</div>
</div>
<div class="csl-entry" style="clear: left; margin-bottom: 1em;">
<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
15. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
Hofbauer J. Forty Years of Postpituitary Extract in Obstetrics. <i>American Journal of Obstetrics and Gynecology</i>. 1955;69(4):822-825. doi:<a href="https://doi.org/10.1016/S0002-9378(16)38084-X">10.1016/S0002-9378(16)38084-X</a></div>
</div>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.type=webpage&rft.title=J.%20Isfred%20Isidor%20Hofbauer&rft.description=Photograph%20of%20J.%20Isfred%20Isidor%20Hofbauer"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.type=newspaperArticle&rft.title=Dr.%20Isfred%20Hofbauer%2C%20a%20Gynecologist%2C%2089&rft.source=New%20York%20Times&rft.rights=Copyright%20New%20York%20Times%20Company%20Mar%2015%2C%201961&rft.identifier=https%3A%2F%2Fsearch.proquest.com%2Fdocview%2F115275211%2Fcitation%2F2FE7932C782C4BB3PQ%2F1&rft.aufirst=Special%20to%20The%20New%20York&rft.aulast=Times&rft.au=Special%20to%20The%20New%20York%20Times&rft.date=1961&rft.pages=39&rft.issn=03624331"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_id=urn%3Aisbn%3A978-1-108-33671-0%20978-1-108-42170-6&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Eponyms%20and%20Names%20in%20Obstetrics%20and%20Gynaecology&rft.publisher=Cambridge%20University%20Press&rft.edition=3&rft.aufirst=Thomas%20F.&rft.aulast=Baskett&rft.au=Thomas%20F.%20Baskett&rft.date=2019-01-31&rft.isbn=978-1-108-33671-0%20978-1-108-42170-6"></span>
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<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The%20Cincinnati%20Lancet-clinic&rft.publisher=J.C.%20Culbertson&rft.date=1904&rft.tpages=794&rft.language=en"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_id=info%3Adoi%2F10.1001%2Fjama.1897.02440360016002e&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=THE%20NATURE%20OF%20THE%20LEUCOCYTOSIS%20PRODUCED%20BY%20NUCLEINIC%20ACID%3B%20A%20PRELIMINARY%20EXPERIMENTAL%20STUDY.&rft.jtitle=JAMA%3A%20The%20Journal%20of%20the%20American%20Medical%20Association&rft.stitle=JAMA&rft.volume=XXIX&rft.issue=10&rft.aufirst=Delano&rft.aulast=Ames&rft.au=Delano%20Ames&rft.date=1897-09-04&rft.pages=472&rft.issn=0098-7484&rft.language=en"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The%20American%20Journal%20of%20Obstetrics%20and%20Diseases%20of%20Women%20and%20Children&rft.publisher=W.A.%20Townsend%20%26%20Adams&rft.date=1903&rft.tpages=934&rft.language=en"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Grundz%C3%BCge%20einer%20Biologie%20der%20menschlichen%20Plazenta%2C%20mit%20besonderer%20berucksichtigung%20Fragen%20der%20f%C3%B6talen%20Ern%C3%A4hrung&rft.place=Wien&rft.publisher=W.%20Braum%C3%BCller&rft.aufirst=Jsidro.&rft.aulast=Hofbauer&rft.au=Jsidro.%20Hofbauer&rft.date=1905&rft.tpages=xii%2C%20175%20p."></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Archives%20of%20Internal%20Medicine&rft.publisher=American%20Medical%20Association.&rft.date=1923&rft.tpages=966&rft.language=en"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_id=info%3Adoi%2F10.1016%2FS0002-9378(25)90514-5&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=The%20function%20of%20the%20hofbauer%20cells%20of%20the%20chorionic%20villus%20particularly%20in%20relation%20to%20acute%20infection%20and%20syphilis&rft.jtitle=American%20Journal%20of%20Obstetrics%20and%20Gynecology&rft.stitle=American%20Journal%20of%20Obstetrics%20and%20Gynecology&rft.volume=10&rft.issue=1&rft.aufirst=J.&rft.aulast=Hofbauer&rft.au=J.%20Hofbauer&rft.date=1925-07&rft.pages=1-14&rft.spage=1&rft.epage=14&rft.issn=00029378&rft.language=en"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The%20Journal%20of%20the%20Arkansas%20Medical%20Society&rft.publisher=Arkansas%20Medical%20Society.&rft.date=1912&rft.tpages=506&rft.language=en"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Therapeutic%20Notes&rft.publisher=Parke%2C%20Davis%20%26%20Company&rft.date=1912&rft.tpages=368&rft.language=en"></span>
<span class="Z3988" title="url_ver=Z39.88-2004&ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fzotero.org%3A2&rft_id=info%3Adoi%2F10.1016%2FS0002-9378(16)38084-X&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Forty%20Years%20of%20Postpituitary%20Extract%20in%20Obstetrics&rft.jtitle=American%20Journal%20of%20Obstetrics%20and%20Gynecology&rft.stitle=American%20Journal%20of%20Obstetrics%20and%20Gynecology&rft.volume=69&rft.issue=4&rft.aufirst=J.&rft.aulast=Hofbauer&rft.au=J.%20Hofbauer&rft.date=1955-04&rft.pages=822-825&rft.spage=822&rft.epage=825&rft.issn=00029378&rft.language=en"></span>
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<div class="csl-left-margin" style="float: left; padding-right: 0.5em; text-align: right; width: 2em;">
16. </div>
<div class="csl-right-inline" style="margin: 0 .4em 0 2.5em;">
TIMES
WLLS to TNY. GLAND INFLUENCE TRACED IN CANCER: Cell Growth Is Linked
With Pituitary Overfunction in Cases of Mothers. CHECK BY X-RAY REPORTED
Medical Association is Also Told of Many Infections Laid to Sinus
Trouble. <i>New York Times</i>. 1934:16.</div>
</div>
MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com6tag:blogger.com,1999:blog-4138102295975819610.post-43834055902906405032020-05-26T12:12:00.005-07:002020-05-26T12:13:01.543-07:00Is SO2 Polar or Nonpolar?<span style="font-size: large;">Answer: SO2 is a polar molecule because the lone pair of electrons on the central sulfur atom cause electron-electron repulsion that forces a bent structure leading to an unequal distribution of charge throughout the molecule. </span><br />
<span style="font-size: medium;"><br /></span>
<span style="font-size: medium;">Due to the molecules relatively strong dipole, the compound a melting point of -72˚C and a boiling point of -10˚C. This means that SO2 is a gas at standard temperature and pressure. The gas is found at low concentrations in earths atmosphere at less than 1 ppm. It features more prominently on the atmospheres of other plants. For example, Venus has an atmospheric concentration of 150 ppm SO2. It can be produced from constituent elements or sulfites. The molecule is said to have a pungent smell- similar to a just-struck match. </span><br />
<span style="font-size: medium;"><br /></span>
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-gjpQm9J4dyA/XmRaHwx4LhI/AAAAAAAABr4/9mvP1oH6jQcAe60i1AtRaDM6Caf6YSxTwCLcBGAsYHQ/s1600/SO2BallAndStick.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="SO2 Ball and Stick" border="0" data-original-height="850" data-original-width="1354" height="400" src="https://1.bp.blogspot.com/-gjpQm9J4dyA/XmRaHwx4LhI/AAAAAAAABr4/9mvP1oH6jQcAe60i1AtRaDM6Caf6YSxTwCLcBGAsYHQ/s640/SO2BallAndStick.webp" title="SO2 Ball and Stick Structure" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">SO2 Ball and Stick Diagram (one of two resonance structures). Made with <a href="https://avogadro.cc/">Avagadro</a>.</td></tr>
</tbody></table>
<span style="font-size: medium;"><b>How is SO2 utilized in the real world?</b></span><br />
<span style="font-size: medium;"><br /></span>
<span style="font-size: medium;"><b>Sulfur dioxide</b> is most commonly utilized as an intermediate in the production of sulfuric acid. It can be used as a preservative for dried fruits and it has played an important role ini wine-making for millennia. On a chemical note it serves as an excellent reducing agent in many reactions and biochemical systems. At lower temperatures it is also utilized as a solvent. It is a major air pollutant.</span>MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com2tag:blogger.com,1999:blog-4138102295975819610.post-32145141596177022612020-05-26T11:43:00.003-07:002020-05-26T11:43:40.245-07:00Is HCl Polar or Nonpolar?<span style="font-size: large;">Answer: HCl is a polar molecule due to the large electronegativity difference between Chlorine (3.16) and hydrogen (2.20). This causes a region of partial positive charge on the hydrogen atom and a region of partial negative charge on the chlorine halide. </span><br />
<br />
Typically the formula HCl can refer to one of two "concepts": the compound hydrogen chloride and hydrochloric acid, the aqueous form of hydrogen chloride. The compound has a melting point of -114˚C and a boiling point of -85˚C. This means that it is a gas at standard temperature and pressure. As mentioned the compound is soluble in water but it is also soluble in slightly less polar molecules such as ethanol and acetone. It is described as having a "pungent" odor. Hydrogen chloride has an in fact quite storied history being originally discovered by alchemists in the middle ages. Today it is recommended that HCl be handled with extreme caution as HCl forms a corrosive acid when inhaled or when in contact with any part of your skin.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-SSw0HdUDHwg/XpExcDiWGlI/AAAAAAAAB8A/o8JmfJmj3NwdgdnT4t6AWEIyhzv5WOnMgCLcBGAsYHQ/s1600/HClBallAndStickDiagram.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="HCl Ball and Stick Diagram" border="0" data-original-height="732" data-original-width="1274" height="366" src="https://1.bp.blogspot.com/-SSw0HdUDHwg/XpExcDiWGlI/AAAAAAAAB8A/o8JmfJmj3NwdgdnT4t6AWEIyhzv5WOnMgCLcBGAsYHQ/s640/HClBallAndStickDiagram.webp" title="HCl Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">HCl Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=313">MolView</a>.</td></tr>
</tbody></table>
<b>How is HCl utilized in the real world?</b><br />
<br />
Basically all of the prominent uses of HCl are for hydrochloric acid. This includes removing impurities from steel, as a reagent in the production of organic products utilized in pharmaceutical manufacturing, pH control and oil processing. The acid is also present within organism's digestive tract to support the process of degrading eaten foodstuffs.<br />
<br />MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-66036868397497663092020-05-24T18:23:00.001-07:002020-05-24T18:23:19.537-07:00Is CF4 Polar or Nonpolar?<span style="font-size: large;">Answer: CF4 is a nonpolar molecule due to the symmetrical tetrahedral structure which cancels out the different electron pulls by the extremely electronegative fluorine atoms. </span><br />
<br />
As a result of its nonpolar character <b>carbon tetrafluoride</b> has a melting point of -184˚C and a boiling point of -128˚C. This means that the compound is a gas at standard temperature and pressure. Due to the large electronegativity difference between fluorine (3.98) and carbon (2.55), the molecule is noted for an incredibly high bond strength. This is due to the partially positive carbon giving the molecular structure some ionic character. In fact carbon-fluoride bonds are noted to be the strongest bonds in organic chemistry. <b>Tetrafluoromethane</b> is naturally produced when you burn any carbon compound in an atmosphere of fluorine. In industrial applications the molecule is produced by combining CCl2F2 and HF.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-wLaYqDfgfF8/XpEv6T-PlXI/AAAAAAAAB7k/egISOh5mGOkc8wRVxsfPbgZ1MAQSEbrkACLcBGAsYHQ/s1600/CF4BallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="CF4 Ball and Stick Diagram" border="0" data-original-height="1000" data-original-width="856" height="640" src="https://1.bp.blogspot.com/-wLaYqDfgfF8/XpEv6T-PlXI/AAAAAAAAB7k/egISOh5mGOkc8wRVxsfPbgZ1MAQSEbrkACLcBGAsYHQ/s640/CF4BallAndStickModel.webp" title="CF4 Ball and Stick Diagram" width="546" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">CF4 Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=6393">MolView</a>.</td></tr>
</tbody></table>
<b>How is CF4 utilized in the real world?</b><br />
<br />
Due to the strength of the C-F bonds the compound is very stable and will only react with extreme elements like pure alkali metals. In industry the molecule is sometimes used as a refrigerant. Therefore CF4 is sometimes called <b>R-14</b>. As with many carbofluorides <b>tetrafluoromethane</b> can be used as a plasma etchant in this case specifically on silicon derivatives. Due to the molecules higher density it can also be utilized in neutron detectors. However these same properties make the structure one of the most persistent and potent greenhouse gases. The high density also means that CF4 will crowd our regular air, leading a risk of asphyxiation in poorly ventilated spaces.MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com1tag:blogger.com,1999:blog-4138102295975819610.post-31449129189151234082020-05-24T10:00:00.001-07:002020-05-24T10:00:15.720-07:00Is CH2Cl2 Polar or Nonpolar?<span style="font-size: large;">Answer: CH2Cl2 is a polar molecule due to the unequal distribution of charge caused by the pull of electrons from the hydrogen atoms to the chlorine atoms due to hydrogen (2.20) have a lower electronegativity than chlorine (3.16). </span><br />
<br />
As a result of strong intermolecular forces caused by its polar properties, <b>Dichloromethane</b> has a melting point of -96.7˚C and a boiling point of 39.6˚C. This makes the compound a liquid at standard temperature and pressure. Although the liquid form is volatile, the compound is widely utilized as a solvent. Even though it does not form a solution with water, it can dissolve a wide variety of organic compounds which is why it is utilized as a solvent. CH2Cl2 is naturally produced in wetlands by macroalgae and in volcanic eruptions; however, the majority of the compound on earth is produced by humans in industrial processes. The structure is said to have a "sweet" aroma.<br />
<br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-fR88NCYVEho/XpEvcfpRsHI/AAAAAAAAB7c/qxU1TB4RKIIbmngnFgroSR0g1FiaA4jiQCLcBGAsYHQ/s1600/CH2Cl2BallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="972" data-original-width="1164" height="534" src="https://1.bp.blogspot.com/-fR88NCYVEho/XpEvcfpRsHI/AAAAAAAAB7c/qxU1TB4RKIIbmngnFgroSR0g1FiaA4jiQCLcBGAsYHQ/s640/CH2Cl2BallAndStickModel.webp" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">CH2Cl2 Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=6344">MolView</a>.</td></tr>
</tbody></table>
<b>How is CH2Cl2 utilized in the real world?</b><br />
<br />
In addition to being used as a solvent CH2Cl2 has been applied in the food industry to decaffeinate coffees and teas. The substance due to its low boiling point can extract mechanical energy from small temperature differences. Furthermore the compound can be used to weld certain plastics together. Although it is considered the least toxic of the simple chlorohydrocarbons, <b>dichloromethane</b> still poses serious health risks to overexposed individuals. Products with "DCM" are generally forced to label this on their packaging. It is believed that CH2Cl2 does not impact the ozone layer because it degenerates before reaching the stratosphere.MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-82176634948679284542020-05-24T09:26:00.003-07:002020-05-24T09:26:39.392-07:00Is CH2O Polar or Nonpolar?<span style="font-size: large;">Answer: CH2O is a polar molecule due to the presence of a very electronegative oxygen (3.44) on one side of the molecule inducing a partial negative charge with the hydrogens carrying a partial positive charge due to hydrogen's lower electronegativity value (2.20).</span><br />
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<b>Formaldehyde</b> has a melting point of -92˚C and a boiling point of -19˚C as a result of its polar character. This means that the compound is a gas at standard temperature and pressure. It is also very soluble within other polar compounds such as water. <b>Formaldehyde</b> is mostly produced by processes in the upper atmosphere which account for 90% of its natural product. Processes such as forest fires and automobile exhaust systems also contribute CH2O to the environment. This molecule has also been found in interstellar space. There are many reactions involving <b>formaldehyde</b> within organic chemistry.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-ZqBeEcVS_MI/XpEulVtBgUI/AAAAAAAAB7Q/RXZO3z7xiAQH1GnHL3oCY0AfgnAPrd-SwCLcBGAsYHQ/s1600/CH2OBallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="CH2O Ball and Stick Diagram" border="0" data-original-height="964" data-original-width="1206" height="510" src="https://1.bp.blogspot.com/-ZqBeEcVS_MI/XpEulVtBgUI/AAAAAAAAB7Q/RXZO3z7xiAQH1GnHL3oCY0AfgnAPrd-SwCLcBGAsYHQ/s640/CH2OBallAndStickModel.webp" title="CH2O Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">CH2O Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=712">MolView</a>.</td></tr>
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<b>How is CH2O utilized in the real world?</b><br />
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The structure is a quite common precursor to many more complex molecules, including resins and finishes. There are a wide variety of niche uses as well including as a disinfectant and in photography. The compound is considered a human carcinogen at higher concentrations although your body naturally produces and requires a certain amount of formaldehyde. Certain countries have in fact banned manufacturing and importation of CH2O. There were also incidents in the 2000s where large quantities of foodstuff were contaminated in countries like Indonesia and Vietnam where the chemical was added to extent the shelf life of products.MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com1tag:blogger.com,1999:blog-4138102295975819610.post-18779204669888049802020-05-24T08:50:00.005-07:002020-05-24T08:50:48.283-07:00Is CH3Cl Polar or Nonpolar?<span style="font-size: large;">Answer: CH3Cl is a polar molecule due to the partial negative dipole induced around the chlorine atom due to chlorine's high electronegativity (3.16) and the partial positive charges on each of the hydrogen atoms (electronegativity for hydrogen: 2.20). </span><br />
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As a result <b>chloromethane</b> has a melting point of -97.4˚C and a boiling point of -23.8˚C. This means that the compound is a gas at standard temperature and pressure. This gas is often produced by the sugar cane industry during the burning of waste. When released it is said to have a lifespan of one to three years before decaying in the atmosphere. It also naturally occurs in marine phytoplankton and other kinds of bacteria which have an enzyme that synthesizes CH3Cl. It also also been detected as a trace gas in the interstellar space. It is described as having a "faint-sweet" odor.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-qZyVIXOMrhk/XpEtr9RObhI/AAAAAAAAB7I/kgaHCFCN4eEaJJqog3y1xxIuW8qLuldIQCLcBGAsYHQ/s1600/CH3ClBallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="CH3Cl Ball and Stick Diagram" border="0" data-original-height="722" data-original-width="1012" height="456" src="https://1.bp.blogspot.com/-qZyVIXOMrhk/XpEtr9RObhI/AAAAAAAAB7I/kgaHCFCN4eEaJJqog3y1xxIuW8qLuldIQCLcBGAsYHQ/s640/CH3ClBallAndStickModel.webp" title="CH3Cl Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">CH3Cl Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=6327">MolView</a>.</td></tr>
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<b>How is CH3Cl utilized in the real world?</b><br />
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It was originally produced in 1835 by boiling a mixture of methanol, sulfuric acid and sodium chloride. This technique is still utilized today as <b>chloromethane</b> is widely utilized in reactions that produce compounds containing carbon, chlorine and silicon. It used to be within refrigerants. As a result the compound is also called <b>Refrigerant-40</b>. However this has been discontinued since the compound is labelled as a carcinogen with the same effects to the central nervous system as alcohol.MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-48428498768973885362020-05-24T08:33:00.002-07:002020-05-24T08:51:41.690-07:00Is HCN Polar or Nonpolar?<span style="font-size: large;">Answer: HCN is a polar molecule due to the large electronegativity difference across the linear molecule. The electronegativity difference between nitrogen (3.04) and hydrogen (2.20) is large enough to qualify this molecule as polar. </span><br />
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As a result the molecule has a relatively high melting point of -13.3˚C and boiling point of 26˚C. This means that the compound is a liquid at standard temperature and pressure. It is able to form solutions with other polar substances such as water and ethanol. It is however extremely poisonous and flammable due to the instability of the triple bond (there are many different electrons packed into this configuration). As a result on the historical uses of <b>hydrogen cyanide</b> was as a chemical weapon in wartime. Today it is mainly utilized in gold and silver mining in order to purify those substances. Furthermore, it is utilized in the process of electroplating these same ions on other electrodes.<br />
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If you are interested in learning more about the lewis dot structure of HCN, feel free to check out <a href="https://www.makethebrainhappy.com/2019/06/the-lewis-dot-structure-for-hcn.html">this article</a>.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-xgmfaCyn2Jk/XpEtPPxs9PI/AAAAAAAAB7A/-x4r7cz8hQgpj-woFyCThcmgPMhjr0U9wCLcBGAsYHQ/s1600/HCNBallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="HCN Ball and Stick Diagram" border="0" data-original-height="618" data-original-width="1438" height="274" src="https://1.bp.blogspot.com/-xgmfaCyn2Jk/XpEtPPxs9PI/AAAAAAAAB7A/-x4r7cz8hQgpj-woFyCThcmgPMhjr0U9wCLcBGAsYHQ/s640/HCNBallAndStickModel.webp" title="HCN Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">HCN Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=768">MolView</a>.</td></tr>
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<b>Where does hydrogen cyanide occur naturally?</b><br />
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HCN occurs in many different places in minute concentrations which ensures relatively low toxicity. For example there is a small quantity within the pits of dried fruits such as apples, apricots and cherries. Phagocytes within the human body also naturally produce HCN when they are destroying a certain particulate. It also has been detected in Tobacco smoke. However some of the most interesting theories concern the natural occurence of HCN in space. It naturally forms in interstellar clouds as a compound of pure elements. It has also been detected in the moons of other planets such as the moon Titan.MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-68305701232594789122020-05-23T18:39:00.000-07:002020-05-23T18:39:30.538-07:00Convert a CSV Line to a List in Scratch Welcome back to Scratch 101! In this lesson we will be converting a line from a CSV file (comma-separated value) into a Scratch list utilizing a quick data conversion program.<br />
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<b>Objective: </b>Learn how to utilize conditionals, iteration, string operations and lists to convert one data type to another data type.<br />
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<b>Final Product: </b>The reason why CSV files are called "comma-separated" is because the data is separated by comments as shown in the screenshot below.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-muuoG7k-X8s/XsmN2dxq1VI/AAAAAAAACBE/SQ_ypkuoOzoc1hLDd0jsyRwkfZga5ISAACLcBGAsYHQ/s1600/Screen%2BShot%2B2020-05-23%2Bat%2B4.52.33%2BPM.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="338" data-original-width="910" height="236" src="https://1.bp.blogspot.com/-muuoG7k-X8s/XsmN2dxq1VI/AAAAAAAACBE/SQ_ypkuoOzoc1hLDd0jsyRwkfZga5ISAACLcBGAsYHQ/s640/Screen%2BShot%2B2020-05-23%2Bat%2B4.52.33%2BPM.webp" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Example CSV file</td></tr>
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This represents the general structure of a CSV file: the top line contains headers defining each parameter and then each line afterwards contains the data for these parameters for each subject/individual within the dataset. This kind of 2D storage is extremely important and matrices form the basis of complex data science.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-hbHpvU0vg4s/XsnPwrh6TmI/AAAAAAAACBc/MK3RqmfjV_oxfkTdm5kLtBwLIXNSdRkVgCLcBGAsYHQ/s1600/Screen%2BShot%2B2020-05-23%2Bat%2B9.36.29%2BPM.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="544" data-original-width="716" height="486" src="https://1.bp.blogspot.com/-hbHpvU0vg4s/XsnPwrh6TmI/AAAAAAAACBc/MK3RqmfjV_oxfkTdm5kLtBwLIXNSdRkVgCLcBGAsYHQ/s640/Screen%2BShot%2B2020-05-23%2Bat%2B9.36.29%2BPM.webp" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Final Program GUI (Graphical User Interface).</td></tr>
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The program you will create takes a line of "CSV-input" and splits each piece of data into a single Scratch list as shown in the screenshot above.<br />
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<b>Graphical Template:</b> <a href="https://scratch.mit.edu/projects/398509123/">https://scratch.mit.edu/projects/398509123/</a><br />
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<b>Scripts:</b><br />
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<a href="https://1.bp.blogspot.com/-Bxtl9bCYFz4/XsmRDkDaBZI/AAAAAAAACBQ/3k84gCKJELYq4fFiJI2ccEL9Mzz3P3jSQCLcBGAsYHQ/s1600/Screen%2BShot%2B2020-05-23%2Bat%2B5.09.09%2BPM.webp" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="964" data-original-width="1264" height="488" src="https://1.bp.blogspot.com/-Bxtl9bCYFz4/XsmRDkDaBZI/AAAAAAAACBQ/3k84gCKJELYq4fFiJI2ccEL9Mzz3P3jSQCLcBGAsYHQ/s640/Screen%2BShot%2B2020-05-23%2Bat%2B5.09.09%2BPM.webp" width="640" /></a></div>
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<b>Testing</b>: Here is some sample data that you can utilize to test our your program:<br />
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clientid,date,weekdays,gains,prices,up<br />
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1951,3173,26.56,0.7,19.76,0.98,1<br />
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0.00,0.25,-1.27,0.28,2.00,-0.61</div>
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"YEAR","WORLDCONSUMPTION","COPPERPRICE","INCOMEINDEX","ALUMPRICE","INVENTORYINDEX","TIME"</div>
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It's always important to utilize real testing data in order to debug your program. These sets are small enough where you could make the list yourself so you'll be able to spot any mistakes pretty quickly!</div>
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<b>Completed Program</b>: <a href="https://scratch.mit.edu/projects/393399539/">Link</a><br />
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<br />MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com1tag:blogger.com,1999:blog-4138102295975819610.post-16037044453941592522020-05-21T12:00:00.001-07:002020-05-21T12:00:07.282-07:00Is N2 Polar or Nonpolar?<span style="font-size: large;">Answer: N2 is a nonpolar molecule because there is no electronegativity difference across the linear structure because the molecules are identical. This means that there are no permanent dipoles within the structure. </span><br />
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<b>Nitrogen</b> is one of the most important elements on earth since it has a wide variety of applications. Due to the nonpolar properties and relatively few electrons, the compound has a quite low melting point of -210˚C and a boiling point of -196˚C. This means that the compound is a gas at standard temperature and pressure. It makes up about 78% of earth's atmosphere. Lavoisier, who is most noted for <a href="https://www.makethebrainhappy.com/2020/05/is-o2-polar-or-nonpolar.html">discovering oxygen (O2)</a>, gave the compound the name azote which is what the compound is called in many languages in the present day.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-I5OIxtLL9Wg/XpEsy5ko_CI/AAAAAAAAB64/Fi91hLRx8FQ2Ll_czWJVokZT9QLy_8BpACLcBGAsYHQ/s1600/N2BallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="N2 Ball and Stick Diagram" border="0" data-original-height="540" data-original-width="1008" height="342" src="https://1.bp.blogspot.com/-I5OIxtLL9Wg/XpEsy5ko_CI/AAAAAAAAB64/Fi91hLRx8FQ2Ll_czWJVokZT9QLy_8BpACLcBGAsYHQ/s640/N2BallAndStickModel.webp" title="N2 Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">N2 Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=947">MolView</a>.</td></tr>
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<b>How is nitrogen (N2) utilized in the real world?</b><br />
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Although nitrogen is approx. 78% of the atmosphere, only 3% of the compounds in the human body involve nitrogen of some kind, especially <a href="https://www.makethebrainhappy.com/2020/04/is-nh2-polar-or-nonpolar.html">amine groups</a>. However this is enough for an entire nitrogen cycle to exist which filters these nitrogen-containing molecules through an entire cycle between earth and atmosphere. It is utilized in fertilizers for agricultural applications. Liquid nitrogen is commonly utilized as a refrigerant to keep items in especially freezing conditions. Nitrogen-containing compounds even make up the material that we know as Kevlar which is an incredibly strong and durable protective shield. There are some many ways that N2 is utilized however these applications often rely on nitrogen-containing compounds rather than pure nitrogen. Therefore this listing will end; however, we recommend checking out some of our other articles concerning carbon-compounds within the "polarity" series. Click on the "polarity" sidebar tag in order to see the whole selection!MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-35631264894856733302020-05-19T19:44:00.005-07:002020-05-19T19:44:58.959-07:00The Lewis Dot Structure for NO2+<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-bJkdjXqmOxc/XsSUyzwN2II/AAAAAAAACAs/9QTgPqHf3rUjHOYyBeHXFgXoHcQAARYagCLcBGAsYHQ/s1600/Lewis%2BStructure%2Bfor%2BNO2%252B.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Lewis Dot Structure for NO2+" border="0" data-original-height="404" data-original-width="960" height="268" src="https://1.bp.blogspot.com/-bJkdjXqmOxc/XsSUyzwN2II/AAAAAAAACAs/9QTgPqHf3rUjHOYyBeHXFgXoHcQAARYagCLcBGAsYHQ/s640/Lewis%2BStructure%2Bfor%2BNO2%252B.webp" title="Lewis Dot Structure for NO2+" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Created by MakeTheBrainHappy</td></tr>
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Please find the Lewis Dot Structure for NO2+ (also known as nitronium ion) shown above. As with all other Lewis Dot Structures the bonds within the structure can be replaced by two dots. Both of the oxygen's on the ends of NO2+ contain two lone pairs of electrons and are chemically neutral. The +1 positive charge within NO2+ is present on the central nitrogen atom which is the least electronegative species in the molecule (3.04 vs. oxygen's 3.44).<br />
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The presence of this positive charge induces a quite strong attraction for the molecule as a whole to balance this out either with a negatively charged cation or with an extra electron. In fact the NO2 neutral species with an extra electron tacked onto the nitrogen is quite unique in its stability when compared to similar molecules with electrons lacking a pair. If you are interested in learning more about the reaction for forming NO2+, then I would highly recommend this recently published video <a href="https://www.youtube.com/watch?v=5NDHIXwUPeE">lecturing on aromatic ring substitution</a>. </div>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-knPslXEYTUI/XsSWivrdQgI/AAAAAAAACA4/ah-7goSNE2sMhq6dkV4P7F_uWDpHSBnKACLcBGAsYHQ/s1600/NitrationOfSalts.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img border="0" data-original-height="880" data-original-width="646" height="640" src="https://1.bp.blogspot.com/-knPslXEYTUI/XsSWivrdQgI/AAAAAAAACA4/ah-7goSNE2sMhq6dkV4P7F_uWDpHSBnKACLcBGAsYHQ/s640/NitrationOfSalts.webp" width="467" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Different kinds of nitrated benzene rings. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC49564/pdf/pnas01089-0017.pdf">Source</a></td></tr>
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This principle brings us to the second stable conformation of NO2+. As the Lewis Dot Structure reveals, the compound would not exist in a stable form and requires negative charge to balance it out. This can often be supplied by a negative cation such as PF6-, forming a stable nitronium salt. These salts are most often utilized in order to add NO2 species to other molecules such as the benzene rings shown in the diagram above. Researchers in that lab attempted to add NO2 species to benzene rings under different acidic conditions to understand which would be most effective at producing different results.</div>
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<b>Is NO2+ polar or nonpolar?</b></div>
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If you are interested in learning more about this subject, your in luck! We've written an entire article regarding this subject: <a href="https://www.makethebrainhappy.com/2020/04/is-no2-polar-or-nonpolar.html">https://www.makethebrainhappy.com/2020/04/is-no2-polar-or-nonpolar.html</a>. The interesting properties result from the complex interaction between its structure as determined by polarity and its status as a <a href="https://www.makethebrainhappy.com/2018/01/when-an-atom-loses-an-electron-it-becomes.html">cation</a>. This again goes back to the structure as elucidated by the Lewis Dot Structure for NO2+. </div>
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MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com3tag:blogger.com,1999:blog-4138102295975819610.post-60115911441420922212020-05-18T19:10:00.000-07:002020-05-19T07:26:21.533-07:00The Lewis Dot Structure for CH4<div class="separator" style="clear: both; text-align: center;">
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-7O07nTP9w3c/Xr1LW9i9_4I/AAAAAAAAB-o/uUzlNiGITxcO6w3WmflRF5tPDtS9qYU2gCLcBGAsYHQ/s1600/Lewis%2BStructure%2Bfor%2BCH4%2B%25283%2529.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="CH4 Lewis Structure" border="0" data-original-height="485" data-original-width="531" height="584" src="https://1.bp.blogspot.com/-7O07nTP9w3c/Xr1LW9i9_4I/AAAAAAAAB-o/uUzlNiGITxcO6w3WmflRF5tPDtS9qYU2gCLcBGAsYHQ/s640/Lewis%2BStructure%2Bfor%2BCH4%2B%25283%2529.webp" title="CH4 Lewis Structure" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Created by MakeTheBrainHappy.</td></tr>
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The Lewis Dot Structure for CH4 is shown above. These kinds of structures can also be shown by representing each of the bonds with two dots. Each atom in the bond has a full valence, with carbon having access to eight electrons and each hydrogen having access to two (<a href="http://www.makethebrainhappy.com/2018/01/how-many-bonds-can-hydrogen-form.html">this is why</a> hydrogen only needs two). The covalent bonds between the C and the H are similar to the ones <a href="http://www.makethebrainhappy.com/2018/01/how-many-bonds-can-hydrogen-form.html">formed between two Hs</a> because the relatively small difference in electronegativity between carbon and hydrogen.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-qmTEidCP6k0/Xr1L0r1iTOI/AAAAAAAAB-w/8c8H0jFJA9M66bJrLlzYuaFYuI9dV3coQCLcBGAsYHQ/s1600/vsprch4.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Tetrahedral Structure of Methane" border="0" data-original-height="284" data-original-width="274" src="https://1.bp.blogspot.com/-qmTEidCP6k0/Xr1L0r1iTOI/AAAAAAAAB-w/8c8H0jFJA9M66bJrLlzYuaFYuI9dV3coQCLcBGAsYHQ/s1600/vsprch4.webp" title="Tetrahedral Structure of Methane" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 12.8px;">Methane is a tetrahedron structure in 3D space. </span><a href="https://people.uwplatt.edu/~sundin/114/plCH4.htm" style="font-size: 12.8px;">Source</a></td></tr>
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This Lewis Dot Structure also explains some of the fundamental properties of this particle. Since there are no lone pairs on the central atom (or any atom for that matter) there are few dipoles created and the minimal electronegativity difference means that these bonds can essentially be treated as nonpolar covalent bonds. This means that all attraction forces inside the molecule rely on weak London Dispersion Forces which only strengthen in far larger atoms. In fact the molar mass of Methane is so minuscule that it is sometimes mentioned as a possible <a href="http://www.makethebrainhappy.com/2017/08/what-is-lifting-gas.html">lifting gas</a> because its density is less than that of air. It boils at -161˚C due to the weak intermolecular forces present and normally exists as a colorless, odorless gas at STP (Standard Temperatures and Pressures).<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-kJALz4ywIwM/Xr1MH1kn5tI/AAAAAAAAB-4/eDVl-2BuS00zm2OZlOAmSGbWPAU6WzYYwCLcBGAsYHQ/s1600/2_16_methanhydrat.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Methane as a Solid" border="0" data-original-height="713" data-original-width="950" height="480" src="https://1.bp.blogspot.com/-kJALz4ywIwM/Xr1MH1kn5tI/AAAAAAAAB-4/eDVl-2BuS00zm2OZlOAmSGbWPAU6WzYYwCLcBGAsYHQ/s640/2_16_methanhydrat.webp" title="Methane as a Solid" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 12.8px;">Methane in a Solid State. </span><a href="https://worldoceanreview.com/en/wor-1/ocean-chemistry/climate-change-and-methane-hydrates/" style="font-size: 12.8px;">Source</a></td></tr>
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<b>Does Methane exist in other states?</b><br />
<b><br /></b>
Yes- it is theoretically possible to find methane in other states of matter (liquids, solids). But it is extremely rare. Solid Methane is found in hydrates which have trapped methane in a more solid state. Scientists have also theorized that the <a href="https://futurism.com/a-day-swimming-in-the-methane-lakes-of-titan/">lakes of Titan</a>, one of the moons of Saturn, are composed of Liquid Methane. Due to the low boiling and melting points, it is rare to find these other states present.<br />
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<b>Is CH4 an acid or a base?</b><br />
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Methane does not really have classic characteristics of either an acid or a base but it has been classified as a very weak acid. It will not release a hydrogen in solution but it has been shown to release a hydrogen in low-pressure gas mixtures such as the upper atmosphere. However, it should be noted that all of the different species produced in these reactions are extremely unstable.<br />
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<b>Is it soluble in water?</b><br />
<b><br /></b>
No- Methane is not soluble in water because it does not have polar/strong intermolecular forces needed to break the hydrogen-bonds found in water. Therefore is is classified as insoluble. However it is soluble in less polar solutions such as ethanol and acetone to a far greater degree.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-aZ9OeBy1gEo/Xr1MSjqi9uI/AAAAAAAAB-8/x25A5Vpsq_c2mDNvf1UcCCljkGxA4mS2gCLcBGAsYHQ/s1600/methane-stove-burner-01.jpg.653x0_q80_crop-smart.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Methane from a Gas Burner Stove" border="0" data-original-height="433" data-original-width="653" height="424" src="https://1.bp.blogspot.com/-aZ9OeBy1gEo/Xr1MSjqi9uI/AAAAAAAAB-8/x25A5Vpsq_c2mDNvf1UcCCljkGxA4mS2gCLcBGAsYHQ/s640/methane-stove-burner-01.jpg.653x0_q80_crop-smart.webp" title="Methane from a Gas Burner Stove" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 12.8px;">Methane from a gas burner stove. </span><a href="https://www.mnn.com/earth-matters/energy/stories/what-is-methane-and-why-should-you-care" style="font-size: 12.8px;">Source</a></td></tr>
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<b>How do Methane Emissions affect the Earth?</b><br />
<b><br /></b>
<a href="https://www.mnn.com/earth-matters/energy/stories/what-is-methane-and-why-should-you-care">This article</a> should have more information about to answer this question. A common statistic is that methane is a greenhouse gas 84 times more potent than CO2.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-5PT-nt2qzpo/Xr1J2F47XyI/AAAAAAAAB-c/M4XKEll9ttEB6ktft32aD-htMUaheuyRQCLcBGAsYHQ/s1600/Methane-cycle-diagram.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Methane Cycle Diagram" border="0" data-original-height="1071" data-original-width="1600" height="428" src="https://1.bp.blogspot.com/-5PT-nt2qzpo/Xr1J2F47XyI/AAAAAAAAB-c/M4XKEll9ttEB6ktft32aD-htMUaheuyRQCLcBGAsYHQ/s640/Methane-cycle-diagram.webp" title="Methane Cycle Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Methane Cycle. <a href="https://www.britannica.com/science/methane">Source</a></td></tr>
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<b>What are the natural sources of CH4 (methane)?</b><br />
<br />
There are a wide variety of sources that contribute to the cycling of methane within the earth. In terms of natural processes there are different microbes that will either release or take in methane to utilize for cellular metabolism. Most organisms as shown in the diagram are contributing methane to the environment. The imbalance within this cycle is caused by additional methane created through the burning of biomass and fossil fuels. Ultimately these agents react within the atmosphere to form power hydroxide ion oxidizers that are able to take a hydrogen from methane (CH4) - an incredibly difficult task as discussed before in this article in the section about methane as an acid.<br />
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<b>Is CH4 polar or nonpolar?</b><br />
<br />
We've written an entire article on whether CH4 is polar or nonpolar! Feel free to check it out at <a href="https://www.makethebrainhappy.com/2020/02/is-ch4-polar-or-nonpolar.html">this address</a>. As with all questions of polarity, the article examines the statement in terms of the geometric configuration and then tries to see how the varying electronegativities of the different elements impact the ultimate dipole moment. The existence of many elements with extreme electronegativities within one certain molecule can also have an impact!<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-jT9yWkqDVoQ/Xr1NOEav_gI/AAAAAAAAB_M/MFU1MJChBPY8MivNzRNDVpOQT3JrWLcTACLcBGAsYHQ/s1600/PIA19088-MarsCuriosityRover-MethaneSource-20141216.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Methane Cycle on Mars" border="0" data-original-height="1080" data-original-width="1440" height="480" src="https://1.bp.blogspot.com/-jT9yWkqDVoQ/Xr1NOEav_gI/AAAAAAAAB_M/MFU1MJChBPY8MivNzRNDVpOQT3JrWLcTACLcBGAsYHQ/s640/PIA19088-MarsCuriosityRover-MethaneSource-20141216.webp" title="Methane Cycle on Mars" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Methane Cycle on Mars. <a href="https://en.wikipedia.org/wiki/File:PIA19088-MarsCuriosityRover-MethaneSource-20141216.png">Source</a></td></tr>
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<b>How else can be envision the methane cycle?</b><br />
<br />
Scientists have postulated that the methane cycle is also taking place currently on Mars! Although it features different players due to the variable environment and different atmospheric composition, the same principle of sinks and releases are the same. Oftentimes it is postulated that methane is broken down into carbon dioxide and other alcohols instead of remaining as a free species in the atmosphere. For sinks it is most likely held as rock within the soil with the possibility of existing microbes either consuming and releasing methane into the atmosphere!<br />
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<span style="font-size: xx-small;">Sources:</span><br />
<a href="https://pubchem.ncbi.nlm.nih.gov/compound/methane#section=Taste"><span style="font-size: xx-small;">https://pubchem.ncbi.nlm.nih.gov/compound/methane#section=Taste</span></a><br />
<br />MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-73060516285160531642020-05-17T13:11:00.001-07:002020-05-17T13:11:30.026-07:00Is SO3 Polar or Nonpolar?<span style="font-size: large;">Answer: SO3(2-) is a polar molecule due to the lone pair electrons at the "top" of the structure causing electron-electron repulsion and a region of partial negative charge. The resulting bent structure leads to an unequal distribution of charge rotating between the different oxygen molecules depending on which is double-bonded to sulfur and which contain single-bonds at any given moment. </span><br />
<br />
In this article we will be discussing <b>Sulfites</b> that contain a 2- charge as opposed to Sulfur Trioxide which relies on an expanded octet in order to complete its configuration. The latter has no charge either formal or dipole moment since it is a nonpolar molecule with a trigonal planar configuration (i.e. 120˚ between the outer molecules). The former is described by the description right above. SO3(2-) has three resonance structures with one being shown in the diagram below. The other structures move the double bond to another part of the atom with all three positions sharing this extra bond for 1/3 of the time (so each oxygen atoms theoretically has 4/3 of a bond to the central sulfur atom). Although theoretically an acid exists by combining hydrogen atoms, this has only ever been observed in the gas phase of the molecule.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-BqMPyl5l8JI/XpEscfOcwLI/AAAAAAAAB6w/uQBjapK9h2YTf2kwpru4_QBHryXIqRoEACLcBGAsYHQ/s1600/SO3BallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="SO3 Ball and Stick Diagram" border="0" data-original-height="963" data-original-width="1126" height="546" src="https://1.bp.blogspot.com/-BqMPyl5l8JI/XpEscfOcwLI/AAAAAAAAB6w/uQBjapK9h2YTf2kwpru4_QBHryXIqRoEACLcBGAsYHQ/s640/SO3BallAndStickModel.webp" title="SO3 Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">SO3 Ball and Stick Diagram. Created with <a href="https://avogadro.cc/">Avagadro</a>.</td></tr>
</tbody></table>
<b>How is SO3(2-) utilized in the real world?</b><br />
<br />
Sulfites are oftentimes utilized as food additives. They occur naturally in wines, although additional sulfites may be added in order to arrest fermentation and preserve the wine for a long period of time. They may also be utilized as a preservative for other long-lasting consumables such as dried fruit. SO3(2-) oftentimes does not appear in its pure form; rather, it is added ionically-bonded to a salt such as sodium, potassium or calcium. It has been noted that there are specific allergic effects and a higher risk for those with asthma or other respiratory conditions. It is generally regulated that sulfite content be labelled on the packaging of food items. MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com1tag:blogger.com,1999:blog-4138102295975819610.post-89915636788579408742020-05-15T11:37:00.001-07:002020-05-15T11:38:04.749-07:00Library of Congress - By The People Campaign<div>
In the Fall of 2018 the Library of Congress <a href="https://crowd.loc.gov/about/">launched a crowdsourcing website</a> which allowed users to create accounts to transcribe historical documents. This is an excellent and rewarding opportunity for those interested in studying the humanities as you can interact directly with hundreds of thousands of primary source documents.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/--O93ByMc49Q/Xr7ZAFjF9lI/AAAAAAAAB_c/XMRjAjC0rrQ830Fag4UAeHNiNqvHf0DugCLcBGAsYHQ/s1600/Screen%2BShot%2B2019-06-08%2Bat%2B3.59.03%2BPM.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Library of Congress Volunteer Responsibilities " border="0" data-original-height="188" data-original-width="640" height="188" src="https://1.bp.blogspot.com/--O93ByMc49Q/Xr7ZAFjF9lI/AAAAAAAAB_c/XMRjAjC0rrQ830Fag4UAeHNiNqvHf0DugCLcBGAsYHQ/s640/Screen%2BShot%2B2019-06-08%2Bat%2B3.59.03%2BPM.webp" title="Library of Congress Volunteer Responsibilities " width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;"><span style="font-size: 12.8px;">The different responsibilities for volunteers on the website.</span></td></tr>
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Volunteers transcribe, tag and review those transcriptions so that the Library of Congress can publish these on their main site to improve the metadata around certain documents. This will permit historians and researchers to more easily utilize these resources in their studies and make it easier for the general public to access since the documents will be easier to read with a helpful transcription.<br />
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There are currently sixteen different "campaigns" or themes related to women's suffrage, the civil war and even legal documents from the Spanish Empire courtesy of the Law Library of Congress. However, it is nearly guaranteed that the figure for the number of campaigns will soon be outdated given that the librarians are constantly adding in new documents for volunteers to transcribe!<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-J4MTojdFSsw/Xr7a8-ndlMI/AAAAAAAAB_o/lDuDvYakiYUaaoKR898rNKyp2zk49zUrACLcBGAsYHQ/s1600/Screen%2BShot%2B2020-05-15%2Bat%2B2.09.13%2BPM.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Letter from Andrew Johnson to Abraham Lincoln regarding William Wallace" border="0" data-original-height="945" data-original-width="1600" height="376" src="https://1.bp.blogspot.com/-J4MTojdFSsw/Xr7a8-ndlMI/AAAAAAAAB_o/lDuDvYakiYUaaoKR898rNKyp2zk49zUrACLcBGAsYHQ/s640/Screen%2BShot%2B2020-05-15%2Bat%2B2.09.13%2BPM.webp" title="Letter from Andrew Johnson to Abraham Lincoln regarding William Wallace" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Letter from Andrew Johnson to Abraham Lincoln (1863)</td></tr>
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The letter above is one of the coolest in my opinion within the collection. It is a letter from Andrew Johnson to Abraham Lincoln during the former's time as the military governor of Tennessee. It introduces a friend of Johnsons, William Wallace, to the President. When you read one these little-known documents you can imagine yourself as a historian trying to contextualize it within the time period. How do we place this letter within our understanding of the relationship between Johnson and Lincoln? To what extent does William Wallace play a role in acquainting Johnson and Lincoln? To what degree does the letter foreshadow Lincoln's eventual choice of Johnson as his running mate for the 1864 election? You can imagine yourself not just as the transcriber of a letter but as an amateur historian seeking to illuminate this letter and place it within its proper contexts.<br />
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If you are interested in this specific letter you can check it out on the transcription website here: <a href="https://crowd.loc.gov/campaigns/letters-to-lincoln/1865-1889-inauguration-assassination-and-aftermath/mal4014100/">https://crowd.loc.gov/campaigns/letters-to-lincoln/1865-1889-inauguration-assassination-and-aftermath/mal4014100/</a><br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-a3b9cP4Q_j0/Xr7ec6xtEOI/AAAAAAAAB_0/y-k2R5mWT3I9vZbMYL5Xcf4Rf-DKnf4fgCLcBGAsYHQ/s1600/Screen%2BShot%2B2020-05-15%2Bat%2B2.23.46%2BPM.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Letter from William Seward to Mary Todd Lincoln regarding a honor from the French Government" border="0" data-original-height="972" data-original-width="894" height="640" src="https://1.bp.blogspot.com/-a3b9cP4Q_j0/Xr7ec6xtEOI/AAAAAAAAB_0/y-k2R5mWT3I9vZbMYL5Xcf4Rf-DKnf4fgCLcBGAsYHQ/s640/Screen%2BShot%2B2020-05-15%2Bat%2B2.23.46%2BPM.webp" title="Letter from William Seward to Mary Todd Lincoln regarding a honor from the French Government" width="588" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Letter from William Seward to Mary Todd Lincoln.</td></tr>
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A second letter I was excited to transcribe was from William Seward, the U.S. Secretary of State, to Mary Todd Lincoln regarding the honor bestowed by French government upon the widow of the much-beloved Abraham Lincoln. This transcription added on an extra international perspective to the understanding of the different responses to Lincoln's death.<br />
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Like the other letter you can find the whole series on the Library of Congress transcription page: <a href="https://crowd.loc.gov/campaigns/letters-to-lincoln/1865-1889-inauguration-assassination-and-aftermath/mal4364200/">https://crowd.loc.gov/campaigns/letters-to-lincoln/1865-1889-inauguration-assassination-and-aftermath/mal4364200/</a><br />
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This transcription is also published within the main Library of Congress archives: <a href="https://www.loc.gov/resource/mal.4364200/?sp=1&st=text">https://www.loc.gov/resource/mal.4364200/?sp=1&st=text</a><br />
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<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-HqaKXBYAWXY/Xr7fvuMvcqI/AAAAAAAACAA/cNCDAFF6M7czCCLa-sRCmTxTCQkwAGQhgCPcBGAYYCw/s1600/Screen%2BShot%2B2020-05-15%2Bat%2B2.29.00%2BPM.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Published Transcription of the Letter from William Seward to Mary Todd Lincoln." border="0" data-original-height="997" data-original-width="1600" height="398" src="https://1.bp.blogspot.com/-HqaKXBYAWXY/Xr7fvuMvcqI/AAAAAAAACAA/cNCDAFF6M7czCCLa-sRCmTxTCQkwAGQhgCPcBGAYYCw/s640/Screen%2BShot%2B2020-05-15%2Bat%2B2.29.00%2BPM.webp" title="Published Transcription of the Letter from William Seward to Mary Todd Lincoln." width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Published Transcription of the Letter from William Seward to Mary Todd Lincoln.</td></tr>
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And of course <a href="https://crowd.loc.gov/campaigns/letters-to-lincoln/1865-1889-inauguration-assassination-and-aftermath/mal4500052/">the medal is also available as another series for transcription</a>! It certainly paints for a rosy picture of the relationship between France and the United States at this point in time.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-Z1bctuIb0P0/Xr7gOss9NSI/AAAAAAAACAU/PsuHbp-UTIscg2OuW2dKqVhk-Cwmh5pgACLcBGAsYHQ/s1600/Screen%2BShot%2B2020-05-15%2Bat%2B2.04.47%2BPM.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Medal from the French Medal Committee issued to Mary Todd Lincoln." border="0" data-original-height="792" data-original-width="1600" height="316" src="https://1.bp.blogspot.com/-Z1bctuIb0P0/Xr7gOss9NSI/AAAAAAAACAU/PsuHbp-UTIscg2OuW2dKqVhk-Cwmh5pgACLcBGAsYHQ/s640/Screen%2BShot%2B2020-05-15%2Bat%2B2.04.47%2BPM.webp" title="Medal from the French Medal Committee issued to Mary Todd Lincoln." width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Medal from the French Medal Committee issued to Mary Todd Lincoln.</td></tr>
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It is my hope that these few examples from the hundreds of thousands available within the Library of Congress crowdsourcing site illuminate the many hidden gems within these primary source documents. If you are ready to get started, please visit the homepage of the Library of Congress - For the People campaign: <a href="https://crowd.loc.gov/">https://crowd.loc.gov/</a><br />
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MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-33674832657926699562020-05-14T12:21:00.004-07:002020-05-14T12:21:49.278-07:00Is BCl3 Polar or Nonpolar?<span style="font-size: large;">Answer: BCl3 is a nonpolar molecule because the chlorine halides are spaced symmetrically around the central boron atom. This cancels out all of the different polar covalent bond pulls (i.e. between each of the boron-chlorine pairs as caused by the large electronegativity difference between boron (2.04) and chlorine (3.16). </span><br />
<br />
Although the species has zero dipole moment, the presence of an incomplete octet on this species as with other similar molecules such as <a href="https://www.makethebrainhappy.com/2020/03/is-bf3-polar-or-nonpolar.html">BF3</a> and <a href="https://www.makethebrainhappy.com/2020/04/is-bh3-polar-or-nonpolar.html">BH3</a> leads to an inherent instability within the different parts of the compound since Boron lacks a complete octet. This tension is exacerbated by the presence of the incredibly electronegative chlorines (3.16). This causes there to be an unequal distribution of charge within the molecule between the center and the outer edges. As a result BCl3 has a melting point of -107˚C and boiling point of 13˚C. This means that the compound is a gas at standard temperature and pressure. Due to this unequal distribution of general charge the compound is also soluble within slightly polar compounds such as <a href="https://www.makethebrainhappy.com/2020/05/is-ethanol-polar-or-nonpolar.html">ethanol</a> of compounds with similar distribution of charge dispersals such as <a href="https://www.makethebrainhappy.com/2020/02/is-ccl4-polar-or-nonpolar.html">CCl4</a>.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-URq-NVtsBGM/XpErOA7nzYI/AAAAAAAAB6k/tyYZCh57EDsQmm97z8wxsjjSNYyJh_HbACLcBGAsYHQ/s1600/BCl3BallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="BCl3 Ball and Stick Diagram" border="0" data-original-height="1246" data-original-width="1424" height="560" src="https://1.bp.blogspot.com/-URq-NVtsBGM/XpErOA7nzYI/AAAAAAAAB6k/tyYZCh57EDsQmm97z8wxsjjSNYyJh_HbACLcBGAsYHQ/s640/BCl3BallAndStickModel.webp" title="BCl3 Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="font-size: 12.8px;">BCl3 Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=25135">MolView</a>.</td></tr>
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<b>How is BCl3 utilized in the real world?</b><br />
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Many of <b>Boron trichloride's</b> main uses stem from its properties as a strong acid due to the incomplete octet on the central Boron atom. Since it is quite reactive as an acid, it is often utilized to refine a wide variety of metals including Aluminum, Copper and Zinc. In many of these reactions Boron is the true agent and therefore BCl3 is really a source of Boron. The gas is also reactive enough to serve as a component of certain rocket fuels. Furthermore, it is utilized in organic reactions as a reagent in the synthesis of certain organic compounds. However it is noted that the compound should be handled with care because BCl3 will react with water and certain other alcohols to form hydrogen chloride. MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-1286192491950628872020-05-14T11:49:00.001-07:002020-05-14T11:49:16.396-07:00Is O2 Polar or Nonpolar?<span style="font-size: large;">Answer: O2 is a nonpolar molecule due to the linear structure containing two identical molecules with the same electronegativity. Therefore no permanent dipole is induced in any part of the structure. </span><br />
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<b>Oxygen</b> has rich and storied history in its discovery although ultimately its properties of combustion led to these revelations. This was due to oxygen's high electronegativity (3.44). However O2 in its pure form is small and nonpolar. As a result it has a quite low melting point of -219˚C and boiling point of -183˚C. This means that the compound is a gas at standard temperature and pressure. The atmosphere consists of approximately 21% O2.<br />
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To learn more about the lewis dot structure for oxygen, feel free <a href="https://www.makethebrainhappy.com/2019/12/the-lewis-dot-structure-for-o2.html">to read this post</a>. This article also discusses the importance of the oxygen revolution and the importance of oxygen within carbon cycling. <br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-1na8HTxpKuM/XpEpBkxgWjI/AAAAAAAAB6A/Dd6kzShuDQ03ADigTvlFwKrrIDYBgm2SwCLcBGAsYHQ/s1600/O2BallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="O2 Ball and Stick Diagram" border="0" data-original-height="516" data-original-width="1112" height="296" src="https://1.bp.blogspot.com/-1na8HTxpKuM/XpEpBkxgWjI/AAAAAAAAB6A/Dd6kzShuDQ03ADigTvlFwKrrIDYBgm2SwCLcBGAsYHQ/s640/O2BallAndStickModel.webp" title="O2 Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">O2 Ball and Stick Diagram. Created with <a href="http://molview.org/?cid=977">MolView</a>.</td></tr>
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<b>How is O2 utilized in the real world?</b><br />
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There is an incredible variety in the functions of oxygen but its inarguably most important role is within biological organisms. Oxygen serves as the final electron acceptor in the electron transport chain and an important byproduct of photosynthesis. This permits the existence of complex life forms such as humans. This is why it makes sense that oxygen therapy is important in medical treatments. It also finds similar utilizations in low-pressure space suits for astronauts. Within industry the most common usage is in smelting iron ore to steel. It is also used in manufacturing of antifreeze, fabrics and plastics. More niche applications include welding, rocket fuel oxidation, and water treatment.<br />
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<br />MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0tag:blogger.com,1999:blog-4138102295975819610.post-80385589064485619732020-05-13T17:52:00.000-07:002020-05-13T17:52:22.779-07:00Is NO3 Polar or Nonpolar?<span style="font-size: large;">Answer: NO3- is based on its geometric structure technically a nonpolar molecule because the different oxygen atoms are dispersed in a symmetrical manner around the central nitrogen atom. However the presence of extra lone pair electrons on two of the oxygens induces regions of partial negative charge on those oxygen atoms. </span><br />
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Although nitrogen trioxide (NO3) exists, it is so unstable that it has never been isolated in pure form and theoretically only serves as an intermediate in certain reactions. Therefore we will continue this discussion by focusing on the <b>nitrate</b> (NO3-) ion. Within this structure the nitrogen atom has a +1 charge whereas the three oxygen atoms have partial -2/3 charge. The diagram shown below exhibits one possible resonance structure: the second bond will continuously switch b/t the oxygen atoms and end up spending approximately one-third of its time with each. In this manner a partial bond is formed with each oxygen atom. <b>Nitrates</b> commonly form a wide variety of inorganic salts with an ionic character containing many different metal elements. Examples include KNO3 and Fe(NO3)3.<br />
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://1.bp.blogspot.com/-4ufnUq32Syg/XpEpp6S86YI/AAAAAAAAB6I/ea-AWPxrTHcS3O8msnc7cIj57vJ1rhNTQCLcBGAsYHQ/s1600/NO3BallAndStickModel.webp" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="NO3 Ball and Stick Diagram" border="0" data-original-height="1126" data-original-width="1208" height="596" src="https://1.bp.blogspot.com/-4ufnUq32Syg/XpEpp6S86YI/AAAAAAAAB6I/ea-AWPxrTHcS3O8msnc7cIj57vJ1rhNTQCLcBGAsYHQ/s640/NO3BallAndStickModel.webp" title="NO3 Ball and Stick Diagram" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">NO3 Ball and Stick Diagram. Created with <a href="https://avogadro.cc/">Avagadro</a>.</td></tr>
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<b>Where is NO3- commonly found in the real world?</b><br />
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There are a wide range of <b>nitrate</b> sources. It is found in our diets via green foods and cured meats. The salt is present within the earth in relatively high concentrations again in salt form. Indeed some bacteria have even evolved to utilize NO3- as a food source. Within industrial uses nitrates feature prominently as fertilizers in agriculture. They are deemed not toxic but there is a small risk of nitrates degrading to nitrites (<a href="https://www.makethebrainhappy.com/2020/05/is-no2-polar-or-nonpolar.html">NO2-</a>) which are a possible carcinogen.MakeTheBrainHappyhttp://www.blogger.com/profile/03851558877830325525noreply@blogger.com0