Question

A catalyst is used

• A. Only for increasing the rate of a reaction
• B. For altering the rate of a reaction
• C. Only for decreasing the rate of a reaction
• D. For making Gibbs free energy change positive

Answer 1

The correct option is B For altering the rate of a reaction

What does a catalyst do?
A catalyst is a substance that can alter the rate of reaction without itself undergoing any permanent chemical change.

As you saw the mountain analogy in the videos, “A catalyst provides an alternative route for the reaction with a lower or higher activation energy."

They can be classified into two categories.
1. Positive catalyst
2. Negative catalyst.

Positive catalyst – It increases the rate of the reaction.
Negative catalyst – It decreases the rate of the reaction.

It does not change the spontaneity of the reaction.