|Themes > Science > Physics > Thermodynamics > Laws of Thermodynamics Basic Significance > Primarily Condensed Phases > Types of Phase Diagrams|
Phase diagrams are a graphical representation of three types of information:
j = intensive variable; P, T, µ (chemical potential), electrical potential, etc.
q = extensive variable; V, S (entropy), ni (number of moles), Q (charge), etc.
Type 1 Phase Diagramj1 vs j 2
e.g., P vs. T; T vs. µ1
Type 2 Phase Diagramj1 vs. q2/q3 or q2/(q2+q3)
e.g., T vs. n1/n1+ n2 (where n1/n1+ n2 is X1, mole fraction of component 1)
Type 3 Phase Diagramq1/q3 vs. q2/q3
e.g., nO /(nCo + nNi ) vs. nNi/(nCo+ nNi ) for NiO-CoO system