activation energy
energy of activation

It is also the step that must be used to calculate the activation energy.

This material is not stable because of its low activation energy.

You'd have to give it some activation energy before the heat is released.

The concept of an activation energy should not be taken too literally.

I would also like to know how activation energy works.

Your question about "activation energy" is specific enough to give a partial answer.

When using a catalyst the activation energy is made smaller.

The reaction with the lower activation energy will proceed at a greater rate.

Where does the activation energy come from to start the reaction?

I always get this mixed up, that means the activation energy is high right?