How do enzymes make chemical reactions more efficient

By lowering energy of activation of the reaction.

High energy produced during the metabolism of reactant to product. Due to the large free energy of activation, the speeds of uncatalyzed biochemical reactions are often exceedingly slow. Enzymes lower this energy of activation so that more molecules have adequate energy to carry into the transition state to speed up the rate of reaction.

the median of the data is 4.5.