Chemical Thermodynamics Question 219
Question: The difference between heats of reaction at constant pressure and at constant volume for the reaction $ 2C_6H_6(l)+15O_2(g)\to 12CO_2(g)+6H_2O(l) $ at $ 25^{o}C $ in kJ is [IIT JEE 1991; Kerala PMT 2004]
Options:
A) -7.43
B) + 3.72
C) -3.72
D) + 7.43
Show Answer
Answer:
Correct Answer: A
Solution:
$ \Delta H-\Delta E=\Delta nRT $
$ =3\times 8.314\times 298 $
$ =-7432J=-7.43,kJ. $