16.1 Properties of Solutions

• Whether or not a substance dissolves depends upon the nature of the solvent and the solute. Factors that determine how fast a substance dissolves are stirring, temperature, and surface area.
• The amount of solute that dissolves in a given solvent depends upon the temperature and pressure.

16.2 Concentrations of Solutions

• To calculate the molarity of a solution, divide the moles of solute by the volume of the solution in liters.
• Diluting a solution does not change the total number of moles of solute in solution.
• The concentration of a solution in percent is the ratio of the volume of the solute to the volume of the solution times 100% or the ratio of the mass of the solute to the mass of the solution times 100%.

16.3 Colligative Properties of Solutions

• Three colligative properties of solutions are vapor-pressure lowering, freezing-point depression, and boiling-point elevation.
• The magnitude of each colligative property is directly proportional to the number of solute molecules or ions present.

16.4 Calculations Involving Colligative Properties

• Molality and mole fractions are two additional ways of expressing the concentration of a solution.
• Freezing-point depression and boiling-point elevation are proportional to molality.