1. Solutions and Solubility

2. Solution
Mixture that has the same composition, color, density, and taste throughout
Has two parts
Solute – substances being dissolved
Solvent – substance doing the dissolving
Can be gaseous, like the air we breathe, or even solid, like brass and sterling silver

3. Types of solutions
Saturated – contains all solute it can hold at a given temperature
Unsaturated – able to dissolve more solute at a given temperature
Supersaturated – contains more solute than a saturated one. Unstable solution

4. Solubility curve
Saturated
Supersaturated
Unsaturated

5. Solubility curve Any point on a line represents a saturated solution.
In a saturated solution, the solvent contains the maximum amount of solute.
Example
At 90oC, 40 g of NaCl(s) in 100g H2O(l) represent a saturated solution.

6. Solubility curve
Any point below a line represents an unsaturated solution.
In an unsaturated solution, the solvent contains less than the maximum amount of solute.
Example
At 90oC, 30 g of NaCl(s) in 100g H2O(l) represent an unsaturated solution. 10 g of NaCl(s) have to be added to make the solution saturated.

7. Solubility curve
Any point above a line represents a supersaturated solution.
In a supersaturated solution, the solvent contains more than the maximum amount of solute. A supersaturated solution is very unstable and the amount in excess can precipitate or crystallize.
Example
At 90oC, 50 g of NaCl(s) in 100g H2O(l) represent a supersaturated solution. Eventually, 10 g of NaCl(s) will precipitate.

8. Solubility curve
Any solution can be made saturated, unsaturated, or supersaturated by changing the temperature.