Some definitions:
• Physical state = solid, liquid, gas
• Phase = a form of matter that has uniform
chemical composition and physical state
• Equilibria (-
no net
change in system)
(i) mechanical
eg. pressuresP1,P2 connected
P1=P2 after equilibrium achieved.
(ii) thermal eg. bathsT1,T2 connected T1=T2
(iii) chemical eg. DG = 0 - dynamic
• Phase transition = spontaneous
change of
eg. water ® ice phase f(p, T)