CHEM 121 Chapter 8 Winter

Mixtures Heterogeneous mixture: 2 Homogeneous mixture: Solution: Colloid:

Solutions Solution = 3 SoluteSolvent

Types of Solutions Colloids: 4 Suspensions:

Solubility 5 Most ionic and polar substances __________________ Most nonpolar substances _______________________ ___________ can be endothermic or exothermic

Solvation Example: NaCl

Solubility Amount of solute that can dissolve in a given amount of solvent 7 Solubility rules p. 247

Temperature and Solubility 8 As T increases….

Pressure and Solubility

What dissolves? Gases form solutions easily Solids and liquids: 10

Dissolving Rate Different from solubility How to increase dissolving rate:

Concentration 12 Weight Percent = Volume Percent = Weight/Volume Percent =

3-minute Practice The amount of alcohol in a bottle of wine is labeled 13.5% (v/v). How much alcohol is in the entire 750. mL bottle? 13

ppm and ppb 14 Parts per million = =

Molarity 15 Molarity (M) = What is the molarity of the solution created when you dissolve 2.5 g of NaOH in 100. mL of solution?

3-minute Practice 16 How many grams of NaOH would you have to dissolve in water to make 100. mL of a 1.0 M solution?

Dilution Add more water: Volume? 17 Concentration? Amount of solute?Number of moles of solute?

3-minute Practice Suppose you have a 1.0 M NaOH solution, but you want a 200. mL of a 0.25 M NaOH solution. How would you make this solution? 18

Aqueous Reactants You have 250 mL of 1.0 M NaOH. How many moles NaOH? 19 How much 0.2 M H 2 SO 4 solution would you need to completely react the NaOH?

5-minute Practice You have: 200. mL of 2.0 M H 2 SO 4 and 500. mL of 1.5 M NaOH 20 How much water (g) can you make? Hints: 1.Go to moles of each 2.Determine which is limiting!

Electrolytes Electrolyte: Strong electrolyte: 21

Weak Electrolytes and Nonelectrolytes 22 Weak electrolytes: Nonelectrolytes:

Colligative Properties Properties that change based on dissolved concentration 23 Boiling point elevation: Freezing point depression: Osmotic pressure:

5-minute practice You fill a pot with 320. g of NaCl and enough water to total 1.50 L of solution. What is the boiling point of this solution? 24

Membranes Semipermeable: 25

Osmosis Osmosis: 26

Osmotic Pressure pressure needed to prevent net flow of solvent through a semipermeable membrane 27 constant

Dialysis: 28