## Equations

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

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

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

Carlos Gonzales 1H
Posts: 50
Joined: Fri Sep 29, 2017 7:05 am
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### Equations

Could someone explain what the significance of wmax=deltaG is? Why is is important that maximum work is equal to deltaG? Thanks

Mitch Mologne 1A
Posts: 74
Joined: Fri Sep 29, 2017 7:04 am

### Re: Equations

Delta G represent free energy which is essentially saying the energy that is able to perform work. Thus the max amount of work a system can do corresponds to the free energy of the system.

Tasnia Haider 1E
Posts: 55
Joined: Sat Jul 22, 2017 3:01 am

### Re: Equations

G is defined as the maximum non-expansion work under constant temperature and pressure. If work done by the system is negative, DeltaG < w, since G = H-TS = U+PV-TS.
Then DeltaG is the maximum work that may be done.

Anh Nguyen 2A
Posts: 36
Joined: Fri Sep 29, 2017 7:05 am
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### Re: Equations

Only at constant temperature and pressure, wmax=ΔG.
The significance of this equation is that if ΔG of a process at constant temperature and pressure is known then we immediately know how much nonexpansion work it can do. Because in many cases, we are interested in many types of works, not just heating and expanding. For example the break down of glucose in cellular respiration which happens in constant pressure and temperature surrounding and the energy from this reaction is used in nonexpansion work . We can easily calculate the standard ΔG of this reaction and therefore know the amount of maximum work it can do.