Activation Energy

Let's not forget that there are two criteria to be followed, in other to a reaction occur. 

We've already learned about collision geometry.

Well, now, it's time for you to learn about the Activation Energy. But... what is it?

Activation energy, or Ea, is the minimum collision energy required for a successful reaction.

When two particles collide, they will need extra energy to break down their bonds, and to form other bond for their products.

In almost every reaction, only a small number of collisions have sufficient energy for a reaction to occur. 

This collision energy is based on the kinetic energy of the particles that are being collided. 

As you know, temperature is a the measure of the average kinetic energy. 

If you plot the number of collisions in a substance at the given temperature against the kinetic energy of each collision, you get the distribution known as Maxwell-Boltzmann distribution.

The following graphic illustrate the M-B distribution. 

The dotted line indicates the activation energy.

The shaded part of the graph is represents the collisions with equal or greater energy than the activation energy.

As you can observe, they are the minority.