Which statement is true regarding a catalyst? A). A catalyst increases the activation energy for a chemical reaction.
b). A catalyst decreases the difference in energy for a chemical reaction.
c). A catalyst allows the reactants to start at a higher energy level.
d). A catalyst lowers the activation energy for a chemical reaction.

d). A catalyst lowers the activation energy for a chemical reaction.

Explanation:

From the given choices, it is true that a catalyst lowers the activation energy for a chemical reaction.

The activation energy is the energy barrier that must be overcome before a chemical reaction can occur.

Some reactions have very high activation energy and would not occur without the introduction of a catalyst.

The catalyst brings the reactants into contact by removing the energy deficiency in the system.

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