Activation energy, Ea is
the minimum energy required for substances to react. It represents the energy
barrier that has to be overcome before a reaction can take place to form
products.
In a reaction, the reactant
molecules come together and chemical bonds are stretched, broken, and formed in
producing the products.
During this process the
energy of the system increases to a maximum, then decreases to the energy of the
products.
The activation energy is the
difference between the maximum energy and the energy of the reactants; i.e. it
is the energy barrier that has to be overcome for the reaction to proceed.
The activation energy
determines the way in which the rate of the reaction varies with. It is usual
to express activation energies in joules per mole of reactants.
