Question

A reaction is associated with net absorption of 10 kcal of energy. The activation energy of forward reaction is 60 kcal. Identify the suitable conclusions regarding the above reaction.

• A. Activation energy of backward reaction is 50 kcal
• B. Activation energy of backward reaction is 70 kcal
• C. The $K_c$ value increases with increase in temperature
• D. The reaction is a two step reaction.

Answer 1

Answer: (A), (C)

Activation energy of backward reaction is 50 kcal
The $K_c$ value increases with increase in temperature

If activation energy for backward reaction = $E_b$ & activation energy for forward reaction =$E_a$ then,
$E_b$ = $E_a$ - 10
$E_b$ = 60 -10 = 50kcal
Therefore the forward reaction is endothermic and thus $K_c$ increases with increase in temperature.