Chemical Thermodynamics Question 5
Question: The entropy values (in $JK^{-1} mol^{-1}$) of H2(g) = 130.6, Cl2(g) = 223.0 and HCl(g) = 186.7 at 298 K and 1 atm pressure. Then entropy change for the reaction $ {H_{2(g)}}+C{l_{2(g)}}\to 2HC{l_{(g)}} $ is [BHU 2005]
Options:
A) + 540.3
B) + 727.3
C) - 166.9
D) + 19.8
Show Answer
Answer:
Correct Answer: D
Solution:
$ \Delta S^{o}=2S_{HCl}^{o}-(S_{H_2}^{o}+S_{Cl_2}^{o}) $
$ =2\times 186.7-(130.6+223.0)=19.8,J{{K}^{-1}}mo{{l}^{-1}} $
