G vs G knot






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Erik Buetow 1F
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G vs G knot

Postby Erik Buetow 1F » Sun Feb 16, 2020 11:41 pm

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

Postby Gerald Bernal1I » Mon Feb 17, 2020 12:04 am

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

Postby 805422680 » Mon Feb 17, 2020 12:09 am

G naught is explicitly for elements in their standard state.

Alexis Robles 2k
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Re: G vs G knot

Postby Alexis Robles 2k » Mon Feb 17, 2020 12:56 pm

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

anjali41
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Re: G vs G knot

Postby anjali41 » Mon Feb 17, 2020 12:59 pm

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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Re: G vs G knot

Postby Ashley Tran 2I » Mon Feb 17, 2020 1:12 pm

This equation also relates G and G
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Jasmine Vallarta 2L
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Re: G vs G knot

Postby Jasmine Vallarta 2L » Mon Feb 17, 2020 1:17 pm

G knot is under standard conditions

Deepika Reddy 1A
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Re: G vs G knot

Postby Deepika Reddy 1A » Mon Feb 17, 2020 1:34 pm

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

Postby kausalya_1k » Mon Feb 17, 2020 6:43 pm

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

Postby Joowon Seo 3A » Mon Feb 17, 2020 10:06 pm

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

Postby 105335337 » Mon Feb 17, 2020 11:11 pm

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

Robin Cadd 1D
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Re: G vs G knot

Postby Robin Cadd 1D » Tue Feb 18, 2020 11:14 am

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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Re: G vs G knot

Postby Megan Vu 1J » Wed Feb 19, 2020 12:38 pm

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

Postby Renee Grange 1I » Wed Feb 19, 2020 1:34 pm

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

205405339
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Re: G vs G knot

Postby 205405339 » Wed Feb 19, 2020 2:03 pm

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

Postby KaleenaJezycki_1I » Wed Feb 19, 2020 3:27 pm

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.


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