Question

The activation energy for a simple chemical reaction, $A\longrightarrow$ B is $E_{a}$ in forward direction. The activation energy for reverse reaction

• A. can be less than or more than $E_a$
• B. is always double of $E_a$
• C. is negative of $E_a$
• D. is always less than $E_a$

Answer 1

Answer: (A)

can be less than or more than $E_a$

Answer 2

The energy of activation of reverse reaction is less than or more than energy of activation $(E_a)$ of forward reaction
\therefore \hspace15mm ? H=(E_a)_F -(E_a)_R
Because it depends upon the nature of reaction. If $(E_a)_F > (E_a)_R$, reaction is endothermic or $(E_a)_F < (E_a)_R$,reaction is exothermic