question_answer

Carboxylic acids readily dissolve in aqueous sodium bicarbonate, liberating carbon dioxide. Which one of the following is correct?

A)  Free carboxylic acid and its conjugate base are of comparable stability.

B)  The free carboxylic acid is more stable then its conjugate base.

C)  The conjugate base of the carboxylic acid is more stable than the free carboxylic acid.

D)  The conjugate acid of the carboxylic acid is more stable than the free carboxylic acid.

Correct Answer: C

Solution :

\[RCOOH+HCO_{3}^{-}RCO{{O}^{-}}+{{H}_{2}}O+C{{O}_{2}}\]Conjugate base, \[RCO{{O}^{-}}\] is more stable due to resonance. Hence equilibrium shifts in the forward direction.