SOLUTIONS Chapter 15

Solution = homogeneous mixture Solute = gets dissolved Solvent = dissolving agent

A substance that dissolves in a solvent is said to be soluble. These two substances are miscible.

A substance that does not dissolve in a solvent is insoluble. These two substances are immiscible.

Types of Solutions (See Table 15-1, p.454)

Solvation = the process of surrounding solute particles with solvent particles to form a solution. Solute particles must separate from one another and the solute and solvent particles must mix.

“Like dissolves like.” Polar solutes dissolve in polar solvents Nonpolar solutes dissolve in nonpolar solvents

Water is polar and dissolves many ionic and polar substances.

Salt is ionic and dissolves in water.

Table sugar is polar and dissolves in water.

Water is an excellent solvent. It is the “universal solvent.” Solutions made with water are called aqueous solutions.

Factors that affect rate of solvation Stirring the mixture Increasing the surface area of the solute Increasing the temperature of the solvent Increasing the pressure when dissolving a gas

Solubility = maximum amount of solute that will dissolve in a given amount of solvent at a specified temperature and pressure Saturated = maximum amount of solute is dissolved Unsaturated = more solute can be dissolved Supersaturated = contains more dissolved solute than a saturated solution at the same temperature.

Factors that affect solubility Increased Temperature – solubility of solids increases; solubility of gases decreases. Increased Pressure – solubility of gases increases. (This process is called aeration)