Is Methanol Polar or Nonpolar?

Answer: Methanol is a polar molecule due to the presence of a hydroxide (-OH) group capable of hydrogen bonding due to the large electronegativity difference between oxygen (3.44) and hydrogen (2.20). This portion of the structure contains distinct partial negative charges (oxygen) and partial positive charges (hydrogen). 

Due to the presence of the hydroxide group and the minimal number of CH2/CH3 groups, this molecule qualifies as the simplest alcohol with the greatest polar dipole. This allows the molecule to be a liquid with a melting point of -98˚C and a relatively high boiling point of 65˚C. Methanol was originally extracted from wood which is why the substance is often known as wood alcohol. Today the structure is produced mainly as a combination between carbon monoxide (CO) and hydrogen (H2). Please note that methanol is toxic to humans and that even small doses can have devastating effects. The molecule acts on both the central nervous system and the mitochondria of cells, destroying both of these mechanisms and thereby inducing permanent blindness or death. This mostly commonly occurs due to the contamination of drinking alcohol with methanol. 

Methanol Ball and Stick Model
Methanol Ball and Stick Model. Created with MolView.
How is methanol utilized in the real world?

Since methanol is the simplest alcohol, it is often utilized as a precursor in the formation of other more complex molecules. This includes formaldehyde (CH2O), longer hydrocarbons and gasoline. In fact, fuel in the European Union may contain up to 3% methanol and engines theoretically could run on this substance in far larger concentrations. However, this runs into the practical problem that methanol is much more corrosive than other fuel types and therefore may decrease the life of the engine parts. Methanol as a polar solvent also has uses in wastewater treatment and sanitation efforts.

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