Catalysts are involved in all reactions other than combustion.
I. ethane π‘ͺ ethene + hydrogen
II. 4,4-dimethylpent-2-yne + hydrogen π‘ͺ propene + 2-methylpropane
III. nonane π‘ͺ 1-ethyl-3-methylbenzene + Hydrogen
IV. methylbenzene + oxygen π‘ͺ carbon dioxide + water vapour