# Why is the boiling point of CH3COOH higher than that of C2H5OH?

Why is the boiling point of $\ce{CH3COOH}$ higher than that of $\ce{C2H5OH}$ ? Both are polar molecules held by hydrogen bond.

• CH3COOH is more polar. Dec 30 '15 at 8:32
• – user7951
Dec 30 '15 at 12:58

Yes you are correct. The molecules are polar in nature and are bound by intermolecular hydrogen bonding. But you must pay attention to the extent of polarization in both the molecules. Consider the alcohol. Here the carbon bearing the $\ce{-OH}$ group is the only polarizing group present. But for $\ce{CH3COOH}$ , the carbonyl carbon is polarized by an $\ce{-OH}$ group as well an $\ce{=O}$ group attached to it, thus increasing its effective polarization more than the alcohol. Therefore $\ce{CH3COOH}$ has greater boiling point.