For the reaction of A + B ⇌ C the activation energy of the forward reaction is 5kJ and the total energy change for the reaction is -20kJ. What is the activation energy of the reverse reaction? Group of answer choices 25 20 5 15

The activation energy for backward reaction is +25 kJ

Explanation:

For the given chemical equation:

We are given:

Enthalpy of the reaction = -20 kJ

As, the enthalpy of the reaction is negative, the reaction is said to be exothermic in nature.

To calculate the activation energy for the reverse reaction, we use the equation:

where,

= Activation energy of the forward reaction = 5 kJ

= Activation energy of the backward reaction = ?

= Enthalpy of the reaction = -20 kJ

Putting values in above equation, we get:  

Hence, the activation energy for backward reaction is +25 kJ

the correct answer is a

it is the most commonly accepted one