If U, H are functions of T only, then ΔU and ΔH should be zero for isothermal processes(adsbygoogle = window.adsbygoogle || []).push({});

ΔG and ΔA are only defined at constant T (thus define isothermal processes)

ΔG = ΔH – TΔS thus equals -TΔS always (since ΔH=0)?

this makes no sense since from previous calculations I have done in many problems ΔH has nonzero value

similarly, ΔA = ΔU - TΔS= -TΔS?

Please help clear my confusion, thanks.

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# Homework Help: DG is for isothermal thus dH =0?

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