Equilibrium Constant TPR

[bobeanie95]

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Q: The ratio of products to reactants at equilibrium for Reaction 1 will change with a change in the:

A. concentration of ATP
B. standard state gibbs free (delta G not)
C. Temperature
D. Pressure

Can someone help me understand why B is wrong? I was under the impression that "standard state delta G naught" is equal to deltaGnaught=RTlnKeq, thus changing standard state would affect the equilibrium constant. Since the answer was C, how would changing the standard state gibbs free energy not affect the reaction's equilibrium?

 

[salemstein]

Keq is fixed at a given temp. Changing products/reactants will not change K since its a constant. You are confusing K with Q, which does change with differing concentrations.

 

[bobeanie95]

I know why A and D are wrong. I just am confused as to why B is also not a legitimate answer according the equation deltaGnaught=-RTlnK, the variables are related.

Also, according to TAM: As the magnitude of deltaGnaught changes, so does the equilibrium constant. K.

https://www.chem.tamu.edu/class/majors/tutorialnotefiles/gibbs.htm

 

[aldol16]

TPR is wrong, as per usual. What you should always remember is C - that Keq is temperature-dependent. However, you also caught that B is also correct, which says that you understand the concept. In the equation delta G0 = -R*T*lnK, there are only two variables, namely delta G0 and K. R is a constant and T is also constant at standard conditions. Therefore, K and delta G0 are linked by some constant and a change in one necessitates a change in the other. That's the very definition of delta G0!

 

[bobeanie95]

@aldol16 just saw your explanation! thanks a lot !