Match the following:

A) Homogeneous equilibrium	1) ${\text{H}}_2\left(\text{g}\right)+{\text{I}}_2\left(\text{g}\right)\rightleftharpoons 2\text{HI}\left(\text{g}\right)$
B) Heterogeneous equilibrium	2) ${\text{H}}_2\text{O}\left(\text{g}\right)\rightleftharpoons {\text{H}}_2\text{O}\left(l\right)$
C) Physical equilibrium	3) ${\text{CaCO}}_3\text{(s)}\rightleftharpoons \text{CaO(s)}+{\text{CO}}_2\text{(g)}$

The equilibrium is said to be homogeneous if all the reactants and products are in same phase. The example is given below.

               ${\text{H}}_2\left(\text{g}\right)+{\text{I}}_2\left(\text{g}\right)\rightleftharpoons 2\text{HI}\left(\text{g}\right)$

The equilibrium is said to be heterogeneous if all reactants and products are in different phases. The example is given below.

           ${\text{CaCO}}_3\text{(s)}\rightleftharpoons \text{CaO(s)}+{\text{CO}}_2\text{(g)}$    

The equilibrium is said to be physical if only state of the substance is a changed but chemical composition is not changed.

   Ex: ${\text{H}}_2\text{O}\left(\text{g}\right)\rightleftharpoons {\text{H}}_2\text{O}\left(l\right)$