Freezing Point/Melting Point: The temperature at which the liquid
and solid phases of a substance will remain together in equilibrium.
Freezing-Point Depression: When a solute is added to a solvent, the
freezing point of the solvent is lowered. In aqueous solutions, one
mOsm of solute per kilogram of water depresses the freezing point by
1.858 millidegrees Celsius (m°C).
Supercooling: The tendency of a substance to remain in the liquid state
when cooled below its freezing point.
Crystallization Temperature: Aqueous solutions can be induced to
freeze (i.e., crystallize) most reliably when supercooled. When super-
cooled, agitating the solution (freeze pulse) induces crystal formation.
The crystallization temperature is the temperature at which crystalliza-
tion is induced. During crystallization, the heat of fusion raises the tem-
perature of the sample to an ice/water freezing-point plateau.
Heat of Fusion: The heat released when the mobile molecules of a liq-
uid are frozen into rigid ice crystals.
Freezing-Point Plateau: The constant temperature maintained during
the time that ice and liquid exist in isothermal equilibrium after crystal-
lization occurs.
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Advanced
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Micro-Osmometer Model 3320 User’s Guide
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