No Standard Temperature?

[JKetlerP]

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I read that that for dG and dH, there is a standard pressure, but NO standard temperature.

Q1-Why not?

Q2-So...things don't change based on temperature? So in dG=dH-TdS, this relationship will hold true no matter the temperature? How can that be...dG and dH have fixed values, and the entropy is also fixed by whatever the reaction is, no? (meaning, AB(s)->A(g)+B(g) has a set entropy, no?)

How can the reaction hold true for all temperatures?

 

[aldol16]

I don't know where you read that but that's not true. For instance, go to any table of standard enthalpies and energies and you'll find that they're defined for specific temperatures (commonly 298 K). The Gibbs equation does have a temperature dependence and an equation called the Gibbs-Helmhotz equation actually gives a function describing the change in G (dG) with respect to temperature.

 

[JKetlerP]

I've seen it in a few places, and one of them is here, in the first paragraph of this wikipedia article.

Here is a stackExchange Q on it (I don't really get the answer though).