Q. For a reaction $A \rightarrow B$, enthalpy of reaction is -4.2 kJ $mol^{-1}$ and enthalpy of activation is 9.6 kJ $mol^{-1}$. The correct potential energy profile for the reaction is shown in option.
A) [image:2021_Q120_opt_a.png]
B) [image:2021_Q120_opt_b.png]
C) [image:2021_Q120_opt_c.png]
D) [image:2021_Q120_opt_d.png]
Explanation
[Solution] The reaction is exothermic (B lower than A) with an activation barrier only about twice the magnitude of $\Delta H$; profile (a) represents this. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.