Question

In an irreversible process taking place at constant T and P and in which only pressure-volume work is being done, the change in Gibbs free energy (dG) and change in entropy (dS), satisfy the criteria
(a) (dS)_{V, E} < 0, (dG)_{T, P} < 0
(b) (dS)_{V, E} > 0, (dG)_{T, P} < 0
(c) (dS)_{V, E} = 0, (dG)_{T, P} = 0
(d) (dS)_{V, E} = 0, (dG)_{T, P} > 0.

Answer 1

(b) : For spontaneity, change in entropy (dS) must be positive, means it should be greater than zero. Change in Gibbs free energy (dG) must be negative means that it should be lesser than zero. (dS)_{V, E} > 0,(dG)_{T, P} < 0.