Question

For a reversible reaction $A \rightleftharpoons B$, which one of the following statements is wrong from the given energy profile diagram?

• A. Activation energy of forward reaction is greater than backward reaction
• B. The forward reaction is endothermic
• C. The threshold energy is less than that of activation energy
• D. The energy of activation of forward reaction is equal to the sum of heat of reaction and the energy of activation of backward reaction

Answer 1

Answer: (C)

where, $E_a$ = activation energy of forward reaction
$E_a$ = activation energy of backward reaction
The above energy profile diagram shows that
$ E_{a} > E'_{a}$
The potential energy of the product is greater than that of the reactant, so the reaction is endothermic.
$E_a = E_{a} ' + \Delta E$
$E_t = E_{a}$ or $E_t > E_{a}'$