1. Solutions are homogeneous mixtures
2. Solutions are usually a solid dissolved in water. But air is also a solution.
3. Solute dissolves in solvent. Solute is usually a solid or gas. Solvent is liquid.
4. Factors affecting solubility:
A. For solids
1.Temperature: solubility increases with increasing Temp.
2. Pressure does not affect solubility of solids
*3. Nature of the solute and solvent. Polar molecules and ionic compounds dissolve in polar solvents. Non polar molecules dissolve in non polar solvents.
B. For gases:
1. Temperature: Solubility of gases decreases as temp. increases
2. Pressure: As pressure increases solubility of gases increases
3. Nature of solute and solvent: same as A. 3.
5. Unsaturated solutions can still have solute dissolve at a given temp.
6. Saturated solutions: no more solute can dissolve at a given temp. Equilibrium exists. Rate of dissolving = Rate of crystallization
7. Be able to read and interpret Table G
8. Use Table F for solubility rules. This table helps you decide whether a compound dissolves or not. Common use of this table is to ask if a precipitate forms during a double replacement reaction. An insoluble compound would be the precipitate.
9. Colligative properties are properties of a solvent that change when a solute is added.
10. Freezing pt. Depression: water will freeze at a lower temp if there is a compound dissolved in it.
11. Boiling Pt. Elevation: water will boil at a higher temp if a compound’s dissolved in it.
12. Ionic compounds have a greater effect that organic compounds because ionic compounds dissociate into ions and organic compounds do not.
13. Molartiy: by far the most important way to measure the concentration of an aqueous solution. M = mole of solute / liters of solution
14. 1,000 mL = 1 L
15. Boiling points are determined by intermolecular forces the weaker the imf’s the lower the boiling point. Non polar molecules have weak imf’s thus they have low boiling points. Polar molecules have stronger imf’s so they have higher boiling points.