Explain the energy theory

The term "energy theory" is quite broad, but in the context of chemical reactions and energetics, it often refers to Collision Theory. This theory explains how chemical reactions occur at the molecular level. It states that for a reaction to happen, reactant particles must:

1. Collide with each other.
2. Collide with sufficient activation energy (minimum energy required to break bonds and form new ones).
3. Collide with the correct orientation for the reacting parts of the molecules to meet.

These effective collisions lead to the formation of products.