- #1
anisotropic
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- 0
Homework Statement
Calculate the pressure at which graphite spontaneously changes to diamond.
T = 298.15 K (isothermal)
Vdiamond - Vgraphite = -2 x 10-6m3/mol
At 273.15K and 1 bar (105 Pa):
ΔGf graphite = 0
ΔGf diamond = 2.9 kJ/mol
i.e. graphite is the more stable and preferred form of carbon in the above conditions.
Homework Equations
Not really sure here... Could be anything.
Perhaps useful is: G = H - TS
But I don't see where P fits in.
The Attempt at a Solution
Well, I know G will be 0 at the pressure I am trying to identify (i.e. graphite and diamond will be in equilibrium, with equal tendency for the carbon to form either).