NEET-XII-Chemistry
Previous Year Paper year:2017
- #86In which case change in entropy is negative?
(1) Evaporation of water
(2) Expansion of a gas at constant
temperature
(3) Sublimation of solid to gas
(4) 2H(g) ``\longrightarrow `` ``H_2``(g)digAnsr: 4Ans : ( 4 )
Sol. •     ▵ ⇀↽2 2H O H O , S 0v
• Expansion of gas at constant
temperature, â–µS > 0
• Sublimation of solid to gas, ▵S > 0
• 2H(g)  H
2
(g), ▵S < 0 (∵▵n
g
< 0)