## About the unit for standard gibbs free energy of a reaction

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

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

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

Lizzie Zhang 2C
Posts: 31
Joined: Fri Sep 29, 2017 7:05 am

### About the unit for standard gibbs free energy of a reaction

The unit for Standard Gibbs free energy of a reaction is kJ/mol, so does that mean, whenever we see something like N2+2O2-->2NO2, we always need to divide the value that we calculated directly by two to get the standard gibbs free energy of the reaction? what if there are two products and the coefficient before the two products are different? How do we divide that?

Krupa Prajapati
Posts: 50
Joined: Sat Jul 22, 2017 3:00 am

### Re: About the unit for standard gibbs free energy of a reaction

Hi! From looking at some of the answers in the solution manual, I don't think you divide the Gibb's free energy by the coefficient of a molecule in a reaction.

Elizabeth Ignacio 1C
Posts: 39
Joined: Fri Sep 29, 2017 7:07 am

### Re: About the unit for standard gibbs free energy of a reaction

That is only necessary when the question specifically asks, "What is the Gibbs Free Energy for one mole of _____?" and they will specifically tell you which molecule needs to have one mole. If there is more than one product for the equation, all that matters is that the specific molecule they asked for has one mole. Otherwise, it is just as is stated above.