What is Homogeneous and Heterogeneous equilibrium ? Give suitable examples ?

Chemical equilibrium can be classified into two types.
a) Homogeneous equilibrium
b) Heterogeneous equilibrium
Homogeneous equilibrium :
“If all the substances of a reversible reaction are present in a single phase” are known as Homogeneous equilibrium.
Eg :
$\underset{\left(\mathrm{g}\right)}{{\mathrm{H}}_2}+\underset{\left(\mathrm{g}\right)}{{\mathrm{I}}_2}\rightleftharpoons 2{\mathrm{HI}}_{\left(\mathrm{g}\right)}$
$\underset{\left(\mathrm{g}\right)}{{\mathrm{N}}_2}+\underset{\left(\mathrm{g}\right)}{3{\mathrm{H}}_2}\rightleftharpoons 2{\mathrm{NH}}_{3( \mathrm{g})}$
Heterogeneous equilibrium :
“If all the substances of a reversible reaction are not present in a single phase” are known as “Heterogeneous equilibrium”.
Eg : $\underset{\left(\mathrm{s}\right)}{{\mathrm{CaCO}}_3}\rightleftharpoons \underset{\left(\mathrm{s}\right)}{\mathrm{CaO}}+{\mathrm{CO}}_{2( \mathrm{g})}$
$\underset{\left(\mathrm{s}\right)}{{\mathrm{NH}}_4\mathrm{HS}}\rightleftharpoons \underset{\left(\mathrm{g}\right)}{{\mathrm{NH}}_3}+{\mathrm{H}}_2{ \mathrm{S}}_{\left(\mathrm{g}\right)}$
The chemical reactions in which all the substances are not present in a single phase is known as Heterogeneous equilibrium.