Gibbs Free Energy

[jmart]

Ok, so I am studying from the Kaplan books and getting really confused. I get equations with delta G but then they have these two

delta G = RT ln(Q/Keq)

This is just something to memorize, no big deal but here is where I get confused...

delta G not = -RT ln(Keq)

what exactly is delta G not? at standard conditions? So when not the other equation must be used?

I just don't understand why at standard conditions the Q is gone and there is a negative sign??

Maybe this is just something that can not be understood but only memorized

p.s I have heard the symbol that looks like a degree sign called "not" but can't figure out how to spell it

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[NickNaylor]

Yes - the degree symbol/subscript 0 means under standard conditions.

I've never seen the top equation before - I wouldn't worry about. It's usually represented as: delta G = delta G-not + RT ln Q.

 

[h9i9j9]

as cole said, its usually represented as:

delta G = delta G-not + RT ln Q.

However, simple log rules tell you that:

delta G = delta G-not + RT ln Q\
delta G = -RTlnK + RT ln Q
delta G = RT (lnQ-lnK)
delta G = RTln (Q/K)

The equation essentially tells you, if Q were to be different from K, what would the driving force be to push the reaction towards equilibrium.

 

[myPsychAlt]

Bang. Pop.




/so, so sorry.