Which of the following processes takes place with decrease of ent… - Vidyadip

MCQ

Which of the following processes takes place with decrease of entropy?

A
Solid $\to $ gas
B
sugar $+$ water $\to $ solution
✓
$NH_{3(g)} + HCl_{(g)} \to NH_4Cl_{(s)}$
D
$A_{(g)} + B_{(g)} \to $ mixture

✓

Answer

Correct option: C.

$NH_{3(g)} + HCl_{(g)} \to NH_4Cl_{(s)}$

c
The structure of a solid is usually well ordered, the structure of a liquid is less ordered, and that of a gas is quite random. Entropy of mixing is higher than the individual separate reactants. In option $(C)$ two gases changing to the one solid product. The product side is more organised and thus has less entropy.

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