Question

which of the following would change the activation energy of a reaction?
none of these
adding a catalyst
changing the temperature
changing reactants concentrations

Explanation:

A catalyst lowers the activation energy of a reaction by providing an alternative reaction pathway with a lower - energy transition state. Temperature affects the rate of a reaction by increasing the kinetic energy of reactant molecules, but it does not change the activation energy itself. Changing reactants' concentrations affects the frequency of collisions and the reaction rate, but not the activation energy.

Answer:

B. Adding a catalyst