Equation based on equilibrium






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305174946
Posts: 61
Joined: Fri Sep 28, 2018 12:17 am

Equation based on equilibrium

Postby 305174946 » Fri Feb 15, 2019 2:06 pm

Can someone please explain the G=G+RTlnQ equation please. Lavelle wrote Q is reaction quotient not K, is he just emphasizing that its not at equilibrium? I thought it was....?

Samantha Kwock 1D
Posts: 61
Joined: Fri Sep 28, 2018 12:24 am

Re: Equation based on equilibrium

Postby Samantha Kwock 1D » Fri Feb 15, 2019 2:14 pm

The G= G + RTlnQ equation holds true for all reactions, even reactions not at equilibrium. However, for reactions at equilibrium, G=0 and Q=K so G=-RTlnK.

michelle
Posts: 62
Joined: Fri Sep 28, 2018 12:23 am

Re: Equation based on equilibrium

Postby michelle » Fri Feb 15, 2019 4:28 pm

Actually, it should be G=G knot + RTlnQ. It implies that the reaction is not at equilibrium.

EllaBerry
Posts: 68
Joined: Fri Sep 28, 2018 12:29 am

Re: Equation based on equilibrium

Postby EllaBerry » Fri Feb 15, 2019 5:14 pm

You would use the equation with the K when the reaction is at equilibrium. Meanwhile, use the equation with the Q at any time.

katie_sutton1B
Posts: 61
Joined: Fri Sep 28, 2018 12:17 am

Re: Equation based on equilibrium

Postby katie_sutton1B » Fri Feb 15, 2019 7:38 pm

K indicates equilibrium, so you would use that equation for a reaction at equilibrium. You would use Q when it not.

KHuang1L
Posts: 60
Joined: Fri Sep 28, 2018 12:19 am

Re: Equation based on equilibrium

Postby KHuang1L » Sat Feb 16, 2019 12:22 pm

Delta G = Delta G under standard conditions + RTlnQ is used when the reaction is not at equilibrium. When the reaction is at equilibrium, you use the equation delta G under standard conditions = -RTlnK because delta G is equal to zero and the equilibrium constant can be used.


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