Question

The heat of formation of methane at constant pressure is 18.5 kcal at 25 c. The heat at constant volume would be

Answer 1

Answer:

The correct option is D)

Explanation:

The heat of formation at constant pressure is ΔH and that at constant volume is ΔE.

Using the below relation:

ΔH=ΔE+ΔnRT

Δn for the above reaction is −1.

⟹ΔE=ΔH+RT  {∵Δn=−1}

⟹ΔE=18500+1.98×298

⟹ΔE=19090 cal

Hence, Option "D" is the correct answer.