Question

What is Heterogeneous catalysis? Give an example.

Answer 1

The catalysis in which the catalyst and the reactants are present in different phases is called heterogeneous catalysis. A catalyst which exists in different phases from the reactants is known as heterogeneous catalyst.
Example: Hydrogenation of unsaturated compounds catalysed by finely divided metals like Ni, Pd, Pt.
$H_{2}C=C{H}_2\left(g\right)+H_2\left(g\right)\underset{orNi}{\overset{PtorPd}{\to }}{H}_{3}C-C{H}_3\left(g\right)$
Here catalyst is in solid phase whereas reactants and products are in gas phase.