Chemical Thermodynamics Question 325
Question: A vessel contains 100 litres of a liquid X. Heat is supplied to the liquid in such a fashion that heat given = change in enthalpy. The volume of the liquid increases by.2 litres. If the external pressure is 1 ami and 202.6 joules of heat were supplied, then [U= total internal energy]
Options:
A) $ \Delta U=0,,\Delta H=0 $
B) $ \Delta U=+202.6J,,\Delta H=+202.6J $
C) $ \Delta U=-202.6J,,\Delta H=-202.6J $
D) $ \Delta U=0,,\Delta H=+202.6J $
Show Answer
Answer:
Correct Answer: D
Solution:
- $ \Delta H= $ heat given so process is isobaric. $ w=-P_{ext}(\Delta V)=-1\times 2 $ .liter. atm $ =-202.6J $
Hence, $ q=202.6J=\Delta H $ and $ \Delta E=q+w=0 $
