An element exists in two solid phases (labelled P1 and P2).
The standard molar entropies of P1 and P2 are21.9J mol-1 K-1 and 23.3J mol-1 K-1 respectively.
The standard Gibbs energy of formation of P1 is 0.0 kJ mol-1 and that of P2 is +0.15kJ mol-1 at 298 K.
(i) Which is the more stable polymorph at 298K?
(ii) If the temperature is increased (at a constant pressure of 1 bar), at what temperature will a phase transition occur between the two polymorphs?