## Non-spontaneous and spontaneous processes

$\Delta G^{\circ}= \Delta H^{\circ} - T \Delta S^{\circ}$

$\Delta G^{\circ}= -RT\ln K$

$\Delta G^{\circ}= \sum \Delta G_{f}^{\circ}(products) - \sum \Delta G_{f}^{\circ}(reactants)$

Jaira_Murphy_2D
Posts: 31
Joined: Fri Apr 06, 2018 3:00 am

### Non-spontaneous and spontaneous processes

What does a non-spontaneous process need to become spontaneous?

Posts: 60
Joined: Fri Sep 28, 2018 12:16 am

### Re: Non-spontaneous and spontaneous processes

Changing the temperature can make a reaction spontaneous, since increasing temperature will increase entropy. At a certain temperature, the value for Gibbs free energy will become negative and the reaction will be spontaneous.

arif_latif_2G
Posts: 60
Joined: Fri Sep 28, 2018 12:23 am

### Re: Non-spontaneous and spontaneous processes

When ΔH > 0 and ΔS > 0, at high temperatures, reactions are spontaneous.
When ΔH < 0 and ΔS < 0, at low temperatures, reactions are spontaneous.
When ΔH < 0 and ΔS > 0, at all temperatures, reactions are spontaneous.
When ΔH > 0 and ΔS < 0, at all temperatures, reactions are non-spontaneous.