Question

Consider an endothermic reaction $X\, \to \,Y$ with the activation energies $E_b$ and $E_f$ for the backward and forward reactions respectively. In general :

• A. there is no definite relation between $E_b$ and $E_f$
• B. $E_b = E_f$
• C. $E_b > E_f$
• D. $E_b < E_f$

Answer 1

Answer: (D)

$E_b < E_f$

Answer 2

$X\, \to \,Y$ is an endothermic reaction $\Delta H = + ve$ $E_b$ = energy of activation of backward reaction $E_f$ = energy of activation of forward reaction $\Delta H$ = heat of reaction Thus. $\quad$ $\quad$ $E_b = E_f$ +$\Delta H$ Thus $\quad$ $\quad$ $E_b > E_f$