How to Calculate Activation Energy.

Activation energy is the energy needed so that reactants can move together, overcome forces of repulsion, and start breaking bonds.

All chemical reactions, including exothermic reactions, need activation energy to get started.

Formula to calculate activation energy.

E_a = the activation energy of the reaction in J/mol
R = the ideal gas constant = 8.3145 J/K·mol
T₁ and T₂ = absolute temperatures (Kelvin)
k₁ and k₂ = the reaction rate constants at T₁ and T₂

Example:

If,

• K1 = 7.1 x 10^-2
• K2 = 8.9 x 10^-3
• R = 8.3145 J/K·mol
• T1 = 276
• T2 = 308K

Therefore;

Therefore, the activation energy is 45.9kJ/mol.