S.no	Column-I		Column-II		Column-III
I	Irreversible Adiabatic expansion of an ideal gas	i)	$\Delta S_{sys}=+ve$	P)	$\Delta S_{total}=0$
II	Free expansion of an ideal gas	ii)	$\Delta S_{sys}=0$	Q)	$\Delta S_{total}=+ve$
III	Melting of a substance at its Boiling point	iii)	$\Delta G=0$	R)	$\Delta S_{total}=-ve$
IV	Vaporisation at Boiling point	iv)	$\Delta G=-ve$	S)	Isoentropic process