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### Pressure

Posted: Sun Feb 16, 2020 3:39 pm
Does pressure affect free energy? If it does how?

### Re: Pressure

Posted: Sun Feb 16, 2020 3:51 pm
The standard Gibbs Free Energy is calculated using the free energy of formation of each component of a reaction at standard pressure.

The Gibbs free energy equation is dependent on pressure. When a system changes from an initial state to a final state, the Gibbs free energy (ΔG) equals the work exchanged by the system with its surroundings, minus the work of the pressure force.

### Re: Pressure

Posted: Sun Feb 16, 2020 3:51 pm
Yes, if you increase the partial pressure of a product gas, ΔG becomes more positive. If you increase the partial pressure of a reactant gas, ΔG becomes more negative because of the equation ΔG=ΔGo+RTlnQ where Q equals partial pressure of products over the partial pressure of reactants.

### Re: Pressure

Posted: Sun Feb 16, 2020 6:46 pm
So in other words, pressure affects Gibbs Free Energy because it affects the value of Q?