Ea

Ea, or the activation energy, is the minimum amount of energy needed for a chemical reaction to start. Think of it like a hurdle that reactant particles must overcome to transform into products. Even if the reactants are ready, they need enough energy to get over this barrier. If the barrier is high, fewer particles can react at a given temperature, making the reaction slower. Lower activation energy means the reaction can happen more easily and quickly. This concept helps explain why some reactions require heat or other energy inputs to proceed efficiently.