Chemical Thermodynamics Question 480

Question: The difference between the heats of reaction at constant pressure and a constant volume for the reaction $ 2C_6{H_{6( 1 )}}+15{O_{2(g)}}\xrightarrow{{}}12C{O_{2(g)}}+6H_2{O_{(I)}} $ in Kj is :

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 n_{g}RT $

Here $ \Delta n_{g}=12-15=-3 $

Thus, $ \Delta H-\Delta E=-3\times 8.314\times 298=-7.43kJ $



NCERT Chapter Video Solution

Dual Pane