What is defined as the energy required to initiate a reaction?

The term that refers to the energy required to initiate a reaction is activation energy. This energy barrier must be overcome for reactants to transform into products during a chemical reaction. Activation energy is crucial because it represents the minimum energy needed to break bonds in the reactants and form new bonds in the products.

In contrast, potential energy refers to the stored energy in an object due to its position or configuration, such as the energy stored in chemical bonds. Kinetic energy is the energy of motion, which is related to the mass and velocity of an object. Thermal energy pertains to the internal energy of a substance due to the kinetic energy of its molecules, which is not directly about initiating a reaction but rather relates to the overall energy state of a system. Therefore, activation energy is specifically associated with the threshold energy required to start a chemical reaction.