[LHM]

I know that in :delta: G = :delta: H - T :delta: S, it seems like G is dependent on what the temperature is in order to determine whether the reaction is spontaneous or not. But then :delta: S has the unit of J/K*mol, and you always have to multiply the :delta: S by a temperature, so is :delta: S or :delta: G more dependent on temperature?

[rabolisk]

They're all dependent on temperature, and there is no fast rule about how much they will change with respect to temperature.

[LHM]

I don't mean to sound like I'm refuting your answer or anything since I'm the one asking the question, but the reason why I asked was because I saw this question somewhere and they were asking for the largest dependence on temperature, and they said that the answer was :delta: G. Because I wasn't sure if they were right or not since they've been wrong before, and because I didn't see why :delta: G was the answer as opposed to :delta: S, I posted it here, so would you (or anyone) say that :delta: G is the correct answer , and if so, why?

[rabolisk]

My apologies. I must have thought you were talking about  :delta: H vs.  :delta: S.

:delta: G is more dependent on temperature. When you use the equation :delta: G =  :delta: H - T :delta: S, you usually assume that  :delta: H and  :delta: S is independent of temperature. For example, a common question is to give you  :delta: H and  :delta: S and then different temperatures and ask you when the reaction is spontaneous or nonspontaneous. But this must assume that  :delta: H and  :delta: S are independent of temperature, which they are not. Nevertheless, those only change a little, especially in small temperature range. Otherwise, we could not use the equation (we would have to have  :delta: H and  :delta: S at each temperature we are interested in). This shows that those two must not have a huge temperature dependence, whereas we know that  :delta: G does.