Question
The freezing point of benzene decreases by 0.45°C when 0.2 g of acetic acid is added to 20 g of benzene. If acetic acid associates to form a dimer in benzene, percentage association of acetic acid in benzene will be
(Kf for benzene = 5.12 K kg mol–1)
-
64.6%
-
80.4%
-
74.6%
-
94.6%
Solution
D.
94.6%
In benzene
2CH3COOH ⇌ (CH3COOH)2