Q. C(s) + 2H$_2$(g) $\rightarrow$ CH$_4$(g); $\Delta H= -74.8$ kJ mol$^{-1}$ Which of the following diagrams gives an accurate representation of the above reaction? [R → reactants; P → products]
A) [image:2025p1_Q65_opt_a.png]
B) [image:2025p1_Q65_opt_b.png]
C) [image:2025p1_Q65_opt_c.png]
D) [image:2025p1_Q65_opt_d.png]
Explanation
[Solution by Claude - not from source] $\Delta H<0$ means the products lie 74.8 kJ/mol below the reactants, with an activation-energy barrier in between. Diagram (1) shows this. Answer (1). (Judged from the diagrams; verify against the official key.)
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.