Question

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 than 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

Answer 1

Answer: (C)

$RCOOH+NaHC{O}_3\rightleftharpoons RCOONa+H_{2}O$
$+C{O}_2$ Or $RCOOH+HC{O}_3^{-}\rightleftharpoons RCO{O}^{-}+H_{2}O+C{O}_2$
Conjugate base, $RCO{O}^{-}$ is more stable. That is why equilibrium shirts in the forward direction.