Negative Delta G

Moderators: Chem_Mod, Chem_Admin

Posts: 55
Joined: Fri Sep 28, 2018 12:26 am

Negative Delta G

Postby ConnorRazmaDis2I » Mon Feb 25, 2019 11:22 am

Why does a negative Delta G correlate to a spontaneous reaction?

Aarti K Jain 1L
Posts: 30
Joined: Fri Sep 28, 2018 12:20 am

Re: Negative Delta G

Postby Aarti K Jain 1L » Mon Feb 25, 2019 12:11 pm

From the second law of thermodynamics, we know that the natural progression of a system is to an increase in entropy. Therefore, a reaction in which the total entropy naturally increases is spontaneous. In the equation for Gibbs, deltaG = -T[deltaS(tot)] at constant temperature and pressure. As a result, as the change in total entropy increases, Gibbs becomes more negative. That's why a negative deltaG is associated with spontaneity. Hope that helps!

Kayla Vo 1B
Posts: 60
Joined: Fri Sep 28, 2018 12:26 am

Re: Negative Delta G

Postby Kayla Vo 1B » Mon Feb 25, 2019 6:00 pm

Spontaneous reactions release free energy, thus the sign of ΔG must be negative. Looking at the Gibbs free energy equation, when ΔH is negative and ΔS is positive, the sign of ΔG will always be negative and therefore the reaction will be spontaneous at all temperatures.

Return to “Gibbs Free Energy Concepts and Calculations”

Who is online

Users browsing this forum: No registered users and 2 guests