Chemical Thermodynamics Question 270
Question: The heat evolved in the combustion of benzene is given by the equation $ C_6H_6(l)+7\frac{1}{2}O_2(g)\to 3H_2O(l)+6CO_2(g) $
$ \Delta H=781.0,kcalmo{{l}^{-1}} $ Which of the following quantities of heat energy will be evolved when 39 g of benzene is burnt in an open container [MP PET 2000]
Options:
A) 122.25 kcal $ mo{{l}^{-1}} $
B) 390.5 kcal $ mo{{l}^{-1}} $
C) 1562.0 kcal $ mo{{l}^{-1}} $
D) 586.75 kcal $ mo{{l}^{-1}} $
Show Answer
Answer:
Correct Answer: B
Solution:
Heat evolved during burning of $ 39g $
$ C_6H_6=\frac{781.0\times 39}{78}=390.5,kcal,mo{{l}^{-1}} $
