Triple Point (C+80)

  C+80+0 Triple Point: Cooled water in sealed cell exhibits all three phases.
  C+80+2 Freezing liquid Nitrogen.
  C+80+5 Triple Point demo: Water boils under vacuum making ice.
  C+80+10 P.V.T. surface model for water.
  C+80+15 P.V.T. surface model for carbon dioxide.
  C+80+20 Wall chart of isothermals.