Question

Why does the solubility of alcohals in water decrease with increase in molecular mass?

Answer 1

Dear Student,

Alcohols are soluble in water due to formation of hydrogen bonds. The hydroxyl group of alcohol is capable of forming hydrogen bonds with water which results in the solubility of alcohols in water. The alcohols also contain the hydrocarbon chain. Increase in molecular mass means increase in the size of hydrocarbon chain of the alcohol. This means that the non-polar part of the alcohol is increasing which leads to less solubility of alcohol in water. Hence, solubility of alcohols decreases with increasing molecular mass of alcohol.