The $p K_{a}$ of acetic acid is 4.76 in water but about 12.3 in dimethyl sulfoxide (DMSO). The main reason is that

ADMSO is a stronger acid than water
BDMSO destroys the $O - H$ bond of acetic acid
Cacetate is better solvated in DMSO than in water
DDMSO cannot hydrogen-bond to the acetate anion, so the anion is poorly stabilised

Answer: D

Water stabilises the small acetate anion strongly by hydrogen bonding. DMSO is a polar aprotic solvent: it solvates cations well but anions poorly. The conjugate base is therefore much less stabilised in DMSO and the acid ionises far less, giving a higher

p K_{a}

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The pKa​ of acetic acid is 4.76 in water but about 12.3 in dimethyl sulfoxide (DMSO). The main reason is that

Answer: D

More questions on Ortho effect and solvent effects

The $p K_{a}$ of acetic acid is 4.76 in water but about 12.3 in dimethyl sulfoxide (DMSO). The main reason is that