Is CCl4 Polar or Nonpolar?

Answer: CCl4 (carbon tetrachloride) is nonpolar because charge is equally distributed around the molecule in a tetrahedral structure.

Even though the bonds between carbon and chlorine are polar covalent due to the electronegativity difference (2.55 vs. 3.16, respectively), the differences in electron-push-pull is cancelled out by the different chlorine molecules being in a tetrahedral 3D structure around the carbon atom. Since the molecules are equally spaced out, there is no point where enough negative charge would accumulate to create a dipole moment on the molecule (i.e. induce polarity).

This is similar logic for why CH4 is nonpolar with a similar Lewis Dot Structure (https://www.makethebrainhappy.com/2018/03/the-lewis-dot-structure-for-ch4.html). Since the molecule is nonpolar, it is insoluble in water and does not form an aqueous solution. You would expect to see a "water and oil" effect with CCl4 in the bottom layer (since it is denser) and water on the upper layer.

CCl4 Molecule Ball and Stick Model. Created with Molview.
How is CCl4 utilized today? 

At standard temperature and pressure CCl4 is a colorless liquid; it used to be utilized in many varied applications including firefighting and refrigeration. However, due to safety concerns and toxicity to certain organ systems, specifically the central nervous system and liver, carbon tetrachloride has been phased out from all large-scale uses. Therefore, it is unlikely that CCl4 as a pure liquid will be utilized for any specific applications in your daily life at this point in time. [1]

[1] https://pubchem.ncbi.nlm.nih.gov/compound/Carbon-tetrachloride

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