Part 2: External Control of Solubility

Temperature and Pressure

Predictions:

Will solubility increase or decrease with increasing temperature?

Will solubility of a gas increase or decrease with increasing pressure?

Concentration UnitsMolarity

Molality

Mole Fraction

Weight Percent

ppm

ppb

Colligative Propeties: Properties of the solvent that change upon dissolution

Vapor Pressure of water at 20 oC is 20.1 mm Hg. What is the pressure of 100 g water mixed with 100 g ethylene glycol?

Distillation: Changing the composition of a mixture of volatile liquids

Vapor Pressures at 50 oC

Water 99 mm HgEthanol 232 mmHg

Distill a 10% alcohol solution.

Boiling Point Elevation

Freezing Point Depression

Effect of Ions

Which is better at melting ice, per gram, NaCl or CaCl2?