Q. Which of the following equations correctly represents the standard heat of formation $(\mathrm{\Delta}H_{f}^{o})$ of methane?
A) C(diamond)+ $2H_{2}(g) \rightarrow CH_{4}(g)$
B) C(graphite) + $2H_{2}(g) \rightarrow CH_{4}(l)$
C) C(graphite) + $2H(g) \rightarrow CH_{4}(g)$
D) C(graphite) + 4H $\rightarrow CH_{4}(g)$
Explanation
(c)
Standard heat of formation of methane is represented by C(graphite)+2H(g) $= CH_{4}(g)$ because the elements taken are in their standard state
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.