Explanation:
In a chemical equilibrium, there are different reactants and products are involved. For example, reaction equation for self-ionization is as follows.
[tex]H_{2}O \rightleftharpoons H^{+} + OH^{-}[/tex]
This reaction is a chemical equilibrium. Also, nitrogen dioxide when present in equilibrium with nitrogen tetraoxide represents chemical equilibrium.
[tex]2NO_{2} \rightleftarrow N_{2}O_{4}[/tex]
On the other hand, in a physical equilibrium same substance is present in different physical states. For example, when ice is present in equilibrium with water then it shows physical equilibrium.
[tex]H_{2}O(s) \rightleftharpoons H_{2}O(l)[/tex]
And, liquid water present in equilibrium with water vapor also represents physical equilibrium.
[tex]H_{2}O(l) \rightleftarrow H_{2}O(g)[/tex]
