EVERYDAY SCIENCE

Detailed explanation-1: -A catalyst is a substance that increases the rate of a reaction without being used up during the reaction. Catalysts permit reactions to proceed along a lower energy path. The activation-energy barrier for the catalyzed reaction is lower than that of the uncatalyzed reaction.

Detailed explanation-2: -During a chemical reaction, the bonds between the atoms in molecules are broken, rearranged, and rebuilt, recombining the atoms into new molecules. Catalysts make this process more efficient by lowering the activation energy, which is the energy barrier that must be surmounted for a chemical reaction to occur.

Detailed explanation-3: -The catalyst lowers the energy of the transition state for the reaction. Since the activation energy is the difference between the transition state energy and the reactant energy, lowering the transition state energy also lowers the activation energy.

Detailed explanation-4: -A catalyst increases the rate of reaction in both forward and backward directions by providing an alternate pathway with lower activation energy. If the activation energy is reduced, more reactants can cross the energy barrier easily.

Detailed explanation-5: -A catalyst provides an alternative pathway for the reaction, that has a lower activation energy. This means there are now more particles with the activation energy and so the rate will increase. Increasing the temperature has no effect on the activation energy.