How does a catalyst work? using these options...
A. by increasing the temp. of a chemical reaction
B. by decreasing the pressure of a chemical reaction
C. by increasing the concentration of reactants in a reaction
D. by decreasing the activation energy of a reaction



Answer :

D is the answer (activation energy)

Answer: D) By decreasing the activation energy of a reaction

A catalyst is a substance that speed up the rate of chemical reaction without affecting the product of the reaction. They only affect the rate of reaction not the yield of reaction.

Catalyst provide an alternative reaction pathway that has lower activation energy  than that of uncatalysed reaction. It increases the frequency of collision and because of these greater collision which lowers the activation energy of the reaction.