Question

Name the two groups into which phenomenon of catalysis can be divided. Given an example of each group with the chemical equation involved.

Answer 1

The phenomenon of catalysis is basically the ability to increase the rate of a chemical reaction, or more specifically the rate at which equilibrium is attained. This is achieved by employing a catalyst. Catalysis can be divided into two classes;

(i) Homogeneous catalysis:

When the reactant and catalyst are in the same phase

$2S{O}_2\left(g\right)+O_2\left(g\right)\stackrel{NO\left(g\right)}{⟶}2S{O}_3\left(g\right)$

(ii) Heterogeneous catalysis:

When the reactant and catalyst are in a different phase

$N_2\left(g\right)+3H_2\left(g\right)\stackrel{Fe\left(s\right)}{⟶}2N{H}_3\left(g\right)$