## G vs G knot

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

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

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

Erik Buetow 1F
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### G vs G knot

Is there any difference between G and G knot or do they represent the same thing?

Gerald Bernal1I
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### Re: G vs G knot

G knot just means that it is only applicable when the elements in the equation are in their standard state since the knot denotes that it is the Gibbs free energy value at standard state.

805422680
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### Re: G vs G knot

G naught is explicitly for elements in their standard state.

Alexis Robles 2k
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### Re: G vs G knot

G knot means that the elements in the equation are in their standard state.

anjali41
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### Re: G vs G knot

G naught is used for elements in their standard states under normal conditions. G is used for nonstandard conditions.

Ashley Tran 2I
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Joined: Thu Jul 11, 2019 12:17 am

### Re: G vs G knot

This equation also relates G and G$^{\circ}$
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Jasmine Vallarta 2L
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### Re: G vs G knot

G knot is under standard conditions

Deepika Reddy 1A
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### Re: G vs G knot

G knot indicates that the substances in the equation are all in their standard or most pure states. You will get different answers when solving for either G or G knot but they can be related using the equation mentioned before in another answer.

kausalya_1k
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### Re: G vs G knot

G knot is for when everything is in its standard state.
An equation that relates the two terms is deltaG=deltaGknot + RTlnQ

Joowon Seo 3A
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### Re: G vs G knot

$G^{\circ}$ is when the reaction is under standard conditions meaning that the temperature is at 25 C and the pressure is at 1 atm
Regular G is for any temperature and for any pressure

105335337
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### Re: G vs G knot

G Knot is for when the things are at standard state in the world. G is just the G at that specific states.

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### Re: G vs G knot

G is the general term; G knot refers to G under standard state conditions (usually 1 atm and 25 degrees Celsius).

Megan Vu 1J
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Joined: Thu Jul 25, 2019 12:15 am

### Re: G vs G knot

G, or more specifically, delta G, is used in a spontaneous reaction with the energy released that is able to be used as work.

However, delta G is the free energy in a standard state condition.To calculate this, you can use it as a state function by adding or subtracting as a Hess Type approach or from the standard free energy of formation of reactants and products.

Renee Grange 1I
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### Re: G vs G knot

Similar to entropy and enthalpy, G knot is G at standard conditions.

205405339
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### Re: G vs G knot

G knot is under standard conditions. G is the total so it will include G knot

KaleenaJezycki_1I
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### Re: G vs G knot

Gerald Bernal1L wrote:G knot just means that it is only applicable when the elements in the equation are in their standard state since the knot denotes that it is the Gibbs free energy value at standard state.

This is true, and also normally when referring to equilibrium constants (K) and equilibrium quotients (Q); Gnot is when the system is at equilibrium and G is when the system isn't at equilibrium.