II

III

I I. The Nature of Solutions

SolutionsSolutions

A. DefinitionsA. Definitions

Solution - Solution - homogeneous mixture

Solvent Solvent - present in greater amount

Solute Solute - substance being dissolved

A. DefinitionsA. Definitions

Solute Solute - KMnO4 Solvent Solvent - H2O

B. SolvationB. Solvation

Solvation – Solvation – the process of dissolving

solute particles are separated and pulled into solution

solute particles are surrounded by solvent particles

B. SolvationB. Solvation

StrongElectrolyte

Non-Electrolyte

solute exists asions only

- +

salt

- +

sugar

solute exists asmolecules

only

- +

acetic acid

WeakElectrolyte

solute exists asions and

molecules DISSOCIATION IONIZATION

View animation online.

B. SolvationB. Solvation

NONPOLAR

NONPOLAR

POLAR

POLAR

““Like Dissolves Like”Like Dissolves Like”““Like Dissolves Like”Like Dissolves Like”

B. SolvationB. Solvation

Soap/DetergentSoap/Detergent• polar “head” with long nonpolar “tail”• dissolves nonpolar grease in polar water

C. SolubilityC. Solubility

SATURATED SOLUTION

no more solute dissolves

UNSATURATED SOLUTIONmore solute dissolves

SUPERSATURATED SOLUTION

becomes unstable, crystals form

concentration

C. SolubilityC. Solubility

SolubilitySolubility• maximum grams of solute that will

dissolve in 100 g of solvent at a given temperature

• varies with temp• based on a saturated soln

C. SolubilityC. Solubility

Solubility CurveSolubility Curve• shows the

dependence of solubility on temperature

C. SolubilityC. Solubility

Solids are more soluble at...Solids are more soluble at...• high temperatures.

Gases are more soluble at...Gases are more soluble at...• low temperatures &• high pressures (Henry’s Law).• EX: nitrogen narcosis, the “bends,” soda