Corrrect match of I, II, III, IV is

	I	II	III	IV
1)	Pyrolysis	Aromatization	Substitution	Isomerisation
2)	Aromatization	Pyrolysis	Substitution	Isomerisation
3)	Pyrolysis	Isomerisation	Substitution	Aromatization
4)	Isomerization	Aromatization	Pyrolysis	Substitution

Thermal decomposition in presence of catalyst, such as platinum or palladium is called pyrolysis. Lower alkanes and alkenes are formed. n-hexane undergoes pyrolysis when it is treated with Pt along with heat.

2-methyl pentane and 3-methyl pentane are the major products when n-hexane reacts with HCl/anhydrous AlCl₃. In the respective reaction, n-hexane undergoes isomerization.

Hexane sulphonic acid is formed when n-hexane treated with conc. sulphuric acid. This is an example of substitution reaction.

Benzene is formed when n-hexane is treated with Cr₂O₃ at high temperature and pressure.