Question

An exothermic chemical reaction proceeds by two stages. Reactants ${ ->[Stage\, 1] }$ Intermediate ${ ->[Stage\, 2] }$ Products The activation energy of state $I$ is $50 \,kJ$ $mol^{-1}$. The overall enthalpy change for the reaction is $-100 \,kJ$ $mol^{-1}$. Which diagram could represent the energy level diagram for the reaction?

• A.
• B.
• C.
• D.

Answer 1

Answer: (C)

Answer 2

Diagram $\left(c\right)$ represents exothermic reaction with
$E_{a}$ $=200-150=50\, kJ$ $mol^{-1}$ and
$\Delta H$ $=50-150=-100\, kJ$ $mol^{-1}$