Thermodynamics MOC

Phase change

Phase changes occur when Quantitative growth gives way to a qualitative leap. The various phase changes are shown below

graph LR;
  S[Solid]
  L[Liquid]
  G[Gas]
  S==>|Melting|L
  L==>|Freezing|S
  L==>|Vaporisation|G
  G<==>|Condensation|L
  S-->|Sublimation|G
  G-->|Deposition|S

Phase changes occur at specific combinations of Temperature and Pressure, which can be shown in phase diagrams. The energy required to complete a phase change for a given mass, at a given temperature and pressure, is the Heat of transformation.

Diagrams

For 𝑝 >𝑝cr and 𝑇 >𝑇cr, the distinction between liquid and gas break down, giving way to a Supercritical fluid.

Water is a strange case, increasing pressure on a solid changes it to a liquid.

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tidy | SemBr | en