Concept:Carboxylic acids are stronger acids than carbonic acid and can displace it from its salts (like sodium carbonate), leading to the evolution of carbon dioxide gas.
Formula:$$ 2\text{R-COOH} + \text{Na}_2\text{CO}_3 \longrightarrow 2\text{R-COONa} + \text{H}_2\text{O} + \text{CO}_2\uparrow $$
Solution:- Identify the functional groups in the options: A, B, and C are esters, while D is propanoic acid (a carboxylic acid).
- Esters do not react with sodium carbonate to release \( \text{CO}_2 \).
- Propanoic acid reacts with \( \text{Na}_2\text{CO}_3 \) to form sodium propanoate, water, and \( \text{CO}_2 \) gas.
Why other options are incorrect:Esters (options A, B, and C) lack an acidic hydrogen and are neutral compounds; they cannot decompose carbonates.
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