How Does Increasing Pressure Affect the Melting Point of Solids?

AI Thread Summary
Increasing pressure typically raises the melting point of solids, but this discussion highlights the specific scenario where the liquid's specific volume is less than that of the solid. The Clapeyron equation is referenced to analyze the relationship between pressure and temperature changes during phase transitions. The inverse relationship derived suggests that as pressure increases, the temperature required for melting decreases, contradicting common assumptions. The discussion proposes a formula indicating that a positive change in pressure leads to an increase in melting point temperature. Overall, the complexities of pressure's effect on melting points are emphasized, particularly in cases where volume differences between phases are significant.
madbeemer
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How would I show that the melting point of a solid decreases with increasing pressure knowing that the specific volume of the liquid is less than the solid?

dP/dT=delta h / (T delta v) Clapeyron equation

Inverse it:
dT/dP = (T delta v)/delta h
v" < v' : molar volume vapor < mol. volume liquid

Not sure where to go from there
 
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well couldn't you say this:

\Delta P = \frac{L_{f}}{\Delta V} \frac{\Delta T}{T}

and since the change in P and T are inversely proportional, a posotive change in P increases melting point T.

just my $0.01
 
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