For a chemical reaction,the activation energy for the forward reaction is +181 kJ and the activation energy for the backward reaction is +62 kJ.What is the net energy change for the forward reaction?

Question

Quizplus · Accepted Answer

The net energy change for a reaction is given by the difference in energy between the products and the reactants, which is equal to the energy released in the forward reaction minus the energy absorbed in the backward reaction.

Since the activation energy for the forward reaction is higher than the activation energy for the backward reaction, we know that the forward reaction is endothermic (requires energy input), while the backward reaction is exothermic (releases energy).

Therefore, the net energy change for the forward reaction is given by:

Net energy change = energy released in the forward reaction - energy absorbed in the backward reaction

Net energy change = (-181 kJ) - (+62 kJ)
Net energy change = -119 kJ

Since the net energy change is negative, this means that the forward reaction is endothermic and requires an input of energy. The correct answer is therefore (C) +119 kJ, which represents the energy that needs to be absorbed in order for the forward reaction to take place.

For a Chemical Reaction,the Activation Energy for the Forward Reaction