Chemical Thermodynamics Question 340
Question: The latent heat of vapourization of $ \varepsilon $ liquid at 500 K and 1 atm pressure is 10.0 kcal/mol. What will be the change in internal energy $ ( \Delta U ) $ of 3 moles of liquid at the same temperature
Options:
A) $ 13.0kcal/mol $
B) $ -13.0kcal/mol $
C) $ 27.0kcal $
D) $ -7.0kcal/mol $
Show Answer
Answer:
Correct Answer: C
Solution:
$ 3H_2O(l)\to 3H_2O(g); $
$ \Delta n=3,\Delta E=\Delta H-\Delta nRT $
$ =30-3\times \frac{2}{1000}\times 500=27kcal $
