Chemical Thermodynamics Question 4
Question: The enthalpy change for the transition of liquid water to steam, $ \Delta H_{vap}=37.3 kJ mo{{l}^{-1}} $ at $ 373 K $ . The entropy change for the process is [MP PET 1994]
Options:
A) $ 111.9 J mo{{l}^{-1}}{{K}^{-1}} $
B) $ 37.3 J mo{{l}^{-1}} {{K}^{-1}} $
C) $ 100 J mo{{l}^{-1}}{{K}^{-1}} $
D) $ 74.6 J mo{{l}^{-1}}{{K}^{-1}} $
Show Answer
Answer:
Correct Answer: C
Solution:
$ \Delta S_{vap}=\frac{\Delta H_{vap}}{T}=\frac{37.3 KJ mo{{l}^{-1}}}{373K} $
$ =0.1 kJ mo{{l}^{-1}} {{K}^{-1}} $
$ =100J mo{{l}^{-1}} {{K}^{-1}} $ .