
reaction progress with time
A reaction profile shows the variation in energy when reactants come together, form the activated complex known as the transition state, which then results in products.
The difference in energy between reactants and the transition state is known as the activation energy.
The activation energy for a particular reaction depends on the nature of bond-breaking and bond making that occurs in conversion from reactants to transition state.
Reactions that have lower activation energies are faster irrespective of whether they are exothermic or endothermic