PYQ NEET- Chemical Thermodynamics L-7

Question: In which case change in entropy is negative?#

A) Sublimation of solid to gas

B) $2 \mathrm{H}(\mathrm{g}) \rightarrow \mathrm{H}_2(\mathrm{~g})$

C) Evaporation of water

D) Expansion of a gas at temperature

Answer: $2 \mathrm{H}(\mathrm{g}) \rightarrow \mathrm{H}_2(\mathrm{~g})$#

Solution:#

$$ 2 \mathrm{H}(\mathrm{g}) \rightarrow \mathrm{H}_2(\mathrm{~g}) $$

Due to bond formation, entropy decreases.