Show that when different phases are in equilibrium the specific Gibbs energy of each phase is equal.

Using the following data, show the pressure at which graphite and diamond are in equilibrium at a temperature of \(25^{\circ} \mathrm{C}\). The data for these two phases of carbon at \(25^{\circ} \mathrm{C}\) and 1 bar are given in the following table:

It may be assumed that the variation of \(k v\) with pressure is negligible, and the lower value of the solution may be used.
\([17,990\) bar]

Transcribed Image Text:

Specific Gibbs energy, g/(k.l/kg) Specific volume, v/(m/kg) Isothermal compressibility, k/(bar) Graphite 0 0.446 x 10 3 2.96 x 10-6 Diamond 269 0.285x10 0.158 x 10-6