Question

What are the conditions for the spontaneity of a process?

Answer 1

1. The spontaneity of any process depends on three different factors.
2. If the enthalpy change of a process is negative, then the process is exothermic and may be spontaneous. (∆H is negative)
3. If the entropy change of a process is positive, then the process may occur spontaneously. (∆S is positive)
4. The Gibbs free energy which is the combination of the above two (∆H – T∆S) should be negative for a reaction to occur spontaneously, i.e. the necessary condition for a reaction to being spontaneous is ∆H – T∆S < 0
5. For spontaneous process, ∆S_total > 0, ∆G < 0, ∆S < 0