The correct option is
D Dimerization of acetic acid in benzene
(a) Ice is less dense than water due to open crystal strucutre because of H-bonding.
(b) The basicity of primary amines is more than tertiary amines as after they donate lone pair to
H+, they can form H-bonding with
H2O molecules and get easily stabilized by solvation, whereas in tertiary amines, the stabilization by solvation is very less.
(c) Formic acid is more acidic than acetic acid due to electron donating nature of
CH3 in acetic acid. The
CH3 actually contributes electron density towards the
O−H bond, making it harder to remove the
H+, and making acetic acid a weaker acid than formic acid.
(d) The dimerization of acetic acid in benzene is due to hydrogen bonding.
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