1. Why does acetone dissolve Styrofoam? 1/ both are nonpolar: “Like (nonpolar) dissolves like (nonpolar)”. 2/ Styrofoam is mostly air. acetone

3. E. Adding solute to a solution: 1/ lowers its freezing (or melting) point 2/ raises its boiling point boiling pt = 100 0 C new boil pt. new freez. pt therm. liquid normal: freezing pt = 0 0 C with solute:

4. Ex. Salts are spread on roads to lower the freezing point of water.  more difficult to freeze

5. Ex. A mixture of ethylene glycol, C 2 H 6 O 2, is used as both an antifreeze and a coolant.

6. Note: a/ more solute  more raising and lowering b/ ionic solids do more than molecules Ex. Salt NaCl vs. sugar C 6 H 12 O 6 Na + Cl - 2x as many particles 2 ions 1 molecule

7. 3/ Osmotic pressure is caused by unequal concentrations of solutes in your cells

8. Sports drinks are designed to: 1. make money; and 2. replenish solutes (electrolytes) to prevent cell damage due to osmotic pressure caused by drinking large amts of water.

9. Practice conversions