KCET 2025 Chemistry Paper

To determine the activation energy (Ea) for the reverse reaction from the given graph, we can use the following energy relationship:
∆H=(Ea)‌forward ‌‌‌−(Ea)‌backward ‌
From the graph, we have:
∆H=90‌KJ
(Ea)‌forward ‌=215‌KJ
Plugging these values into the equation, we get:
90=215−(Ea)‌backward ‌
Solving for (Ea)‌backward ‌ :
(Ea)‌backward ‌=215−90=125‌KJ
Therefore, the activation energy for the reverse reaction is 125 KJ .