Question

Which is a characteristic of a catalyst?

• A. It changes the equilibrium point
• B. It initiates the reaction
• C. It alters the rate of a reaction
• D. It increases the average kinetic energy of the molecules

Answer 1

Answer: (C)

A catalyst is a substance which mere presence influences the rate of a chemical reaction without itself undergoing any permanent chemical change. Some characteristics of a catalyst are following
(i) The catalyst does not alter the position of equilibrium.
(ii) Catalyst does not initiate the reaction.
(iii) The catalyst decreases the activation energy of the reaction and hence, increase the rate of reaction.
(iv) Catalyst alters (change) the rate of reaction.
(v) Catalyst are specific in respect of reactions.
$H_{2}O+CO\underset{\text{ or }Ti{O}_2}{\overset{A{l}_2{O}_3}{\leftarrow }}HCOOH\underset{ZnO}{\overset{Cu\text{ or }}{\to }}C{O}_2+H_2$