Key Topics:
- Making a solution
- Understand that there are many kinds of solutions. Although we usually think of water as
the solvent in a solution, solutions can be in any phase, and have as its solute or solvent any phase as well.
- Understand what "like-dissolves-like"
means.
- Why do polar solvents dissolve polar solutes?
- Which intermolecular forces are at play when a solute dissolves? (Or precipitates?)
- You
should be able to look at a potential solute and solvent and discuss whether or not you expect a solution to form based on the magnitudes
of the solvent-solvent, solvent-solute, and solute-solute interactions.
- Understand the energetics of forming a solution, and how the
intermolecular forces between particles make the dissolving process endothermic or exothermic.
- What is the heat of hydration?
{Chapter 13: #2, 5-9, 11-25, 29-34, 35, 36, 41-46, 51-68, 69-76, 77-98, 99, 100, 103, 104, 106, 109-111 }
- Just like with the properties of matter that we talked about from Chapter 11, you should understand that dissolving and recrystallization
reaches a "dynamic equilibrium".
- Use this to determine if a solution is unsaturated, saturated, or supersaturated.
- Dissolving a gas
phase solute in water
- Understand the effect of temperature and partial pressure of the gas on how much of the gas will be dissolved
in solution.
- Be able to use Henry's Law (constants for this equation will always be given)
- Concentration Units!
- This goes back to Chapter 1, your success here is about problem solving , algebra, and manipulating units!
- You
MUST Memorize the important concentration units and their definitions. These are on Table 12.5. (Shown Below)
- You MUST be able to convert between ANY of these units!
- You MUST be able to explain how to make a solution of a given concentration!
- Colligative Properties
- Vapor Pressure Lowering (nonvolatile solute)
- When a nonvolatile solute is added to a solvent, the vapor pressure
of the solution formed is always lower than the pure solvent. You should be able to use dynamic equilibrium and the rate of
vaporization to explain.
- Also, you should be able to use Rault's Law to quantify the vapor pressure.
- Vapor Pressure Change (volatile
solute)
- When both the solute and solvent are volatile, both components contribute to the vapor pressure of a solution.
- If a solution
is ideal, use Rault's Law to calculate the vapor pressure of each component, and then calculate the vapor pressure of the solution.
- Depending on the solute-solvent interactions, the solution may be non-ideal. Be able to explain this and how it will make your
vapor pressure higher or lower than Rault's law predicts.
- Freezing Point Depression and Boiling Point Elevation
- Explain why this occurs
on a molecular level, and be able to calculate the new boiling point or freezing point. (All constants will be given as needed.)
- Osmotic
Pressure
- Define osmosis
- Calculate an osmotic pressure
- van't Hoff Factor (i)
- What is it? Why do you need it?
- Be able to use it in
all previous colligative property calculations.
