What is $DeltaG$ for a solid melting at its normal melting point?

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Answer 1 · 2016-11-12T09:00:27

$DeltaG$ is $0$ for a process at constant $T$ and $P$ .

Since we are looking at the normal melting point of water ice, it means that we are at a constant $T_"nmp"$ and $P_"norm" = "1 atm"$ .

From the Maxwell Relation:

$dG = -SdT + VdP$

But at constant $T$ and $P$ , $dT = 0$ and $dP = 0$ . Therefore:

$color(blue)(DeltaG_"melt") = -S(0) + V(0) = color(blue)(0)$

What is DeltaGDeltaG for a solid melting at its normal melting point?