hmm I really don't know. But the reaction is feasible, and we have the concentrations. Lets suppose i have the equation, how i should go about solving it?
hmm I really don't know. But the reaction is feasible, and we have the concentrations. Lets suppose i have the equation, how i should go about solving it?
I would assume this (didn't check the image, sorry):
A + B <--> C + D
If it is that equation, and its an equilibrium, then at equilibrium ∆G = 0 so ∆G° = -RT lnK and you can work out the equilibrium ratios. Then just decide whether [A] and will increase or decrease to get to that ratio. (That is assuming the ∆G you've been given is in fact ∆G°. If its ∆G instead, you don't have enough information. I don't really trust the notation of whoever gave you the question though!)
If it is that equation, and its an equilibrium, then at equilibrium ∆G = 0 so ∆G° = -RT lnK and you can work out the equilibrium ratios. Then just decide whether [A] and will increase or decrease to get to that ratio. (That is assuming the ∆G you've been given is in fact ∆G°. If its ∆G instead, you don't have enough information. I don't really trust the notation of whoever gave you the question though!)
Hey
Yes, I confirmed it is delta G at standard conditions. I am given the concentration of each species in the question (1M A, 1M B, 0.1 M C, 0.1 M D). So shall I calculate delta G? If so, I got a large negative value, and accordingly, can I say it goes in forward direction? Is this approach correct?
I still feel pretty weak at grasping what's going on in this question :/
Yes, I confirmed it is delta G at standard conditions. I am given the concentration of each species in the question (1M A, 1M B, 0.1 M C, 0.1 M D). So shall I calculate delta G? If so, I got a large negative value, and accordingly, can I say it goes in forward direction? Is this approach correct?
I still feel pretty weak at grasping what's going on in this question :/
My take on this is that the easiest way to tackle it is to use:
ΔG = -RTlnK
To work out K
Then plug in the values given to find out the reaction quotient K'
If K' is larger than K the reaction goes in reverse and vice versa.
If it is that equation, and its an equilibrium, then at equilibrium ∆G = 0 so ∆G° = -RT lnK and you can work out the equilibrium ratios. Then just decide whether [A] and will increase or decrease to get to that ratio. (That is assuming the ∆G you've been given is in fact ∆G°. If its ∆G instead, you don't have enough information. I don't really trust the notation of whoever gave you the question though!)
Many thanks both of you. I utterly got what you mean, and it worked well.
My last question is whether I can simple find delta G and according to that I can decide which side it will favour. In our example, it is negative so forward. What do you think?
Many thanks both of you. I utterly got what you mean, and it worked well.
My last question is whether I can simple find delta G and according to that I can decide which side it will favour. In our example, it is negative so forward. What do you think?
Do you mean to find ΔG at the beginning of the reaction with only A and B present in stoichiometric amounts? (Don't forget that temperature does not feature in standard conditions)
I don't see how this is relevant for your question.
Do you mean to find ΔG at the beginning of the reaction with only A and B present in stoichiometric amounts? (Don't forget that temperature does not feature in standard conditions)
I don't see how this is relevant for your question.
Yes, at that point where we have 1 molar of reactants and 0.1 molar of products. I can calculate delta G for that point and see whether it will occur or not. As I got a negative value, it is feasible and will go towards products. Correct?
I got your point that delta G changes in the course of the reaction, yeah.
Yes, at that point where we have 1 molar of reactants and 0.1 molar of products. I can calculate delta G for that point and see whether it will occur or not. As I got a negative value, it is feasible and will go towards products. Correct?
I got your point that delta G changes in the course of the reaction, yeah.
According to your question the reaction will not start under standard conditions from the reactants A & B
ΔG is positive.
But you know that at equilibrium ΔG = 0
Use the standard ΔG value to work out the equilibrium constant
And do your calculations using the molar amounts given to find the quotient = [C][D]/[A][ B]