Activation energy is the minimum energy that reacting particles must have for a chemical reaction to occur.
Key points:
- Energy barrier: It is like a hill that reactants must climb before turning into products.
- Collision requirement: Only particles with energy equal to or greater than the activation energy can react when they collide.
- Effect on reaction rate:
- Higher activation energy → fewer particles can react → slower reaction.
- Lower activation energy → more particles can react → faster reaction.
- Catalysts: They lower the activation energy, making reactions faster without being consumed.
In short: Activation energy is the “energy threshold” that reactants need to cross for a reaction to happen.