1. Properties of Solutions

2. Do Now:
Get out your memory game from yesterday and play with your group for 10 minutes—there will be a memory challenge tomorrow!

3. Notes Today:
Write down what you believe is most important—you will have one minute per slide just for writing before I explain the content!
These are the first notes of the 9 weeks!

4. Classification of Matter
Solutions are homogeneous mixtures

5. Solute Solvent A solute is the dissolved substance in a solution.
Salt in salt water
Sugar in soda drinks
Carbon dioxide in soda drinks
Solvent
A solvent is the dissolving medium in a solution.
Water in salt water
Water in soda

6. “Like Dissolves Like”
Nonpolar solutes dissolve best in nonpolar solvents
Fats
Benzene
Steroids
Hexane
Waxes
Toluene
Polar and ionic solutes dissolve best in polar solvents
Inorganic Salts
Water
Sugars
Small alcohols
Acetic acid

7. Go here… http://www.dhmo.org/facts.html
Read several sections of information
You have five minutes…

8. Stop n’ Jot Tell me all that you know about dihydrogen monoxide!
We know…

9. Water’s Solvent Interactions
The oxygen (slightly negative) end of the water molecule is attracted to the positive ion of a salt.

10. Water’s Solvent Interactions
The hydrogen (slightly positive) end of the water molecule is attracted to the negative ion of a salt.

11. Solubility Trends
The solubility of MOST solids increases with temperature.
The rate at which solids dissolve increases with increasing surface area of the solid.
The solubility of gases decreases with increases in temperature.
The solubility of gases increases with the pressure above the solution.

12. Therefore… Solids tend to dissolve best when: Heated Stirred
Ground into small particles
Gases tend to dissolve best when:
The solution is cold
Pressure is high

13. Solubility Chart

14. Definition of Electrolytes and Nonelectrolytes
An electrolyte is:
A substance whose aqueous solution conducts an electric current.
A nonelectrolyte is:
A substance whose aqueous solution does not conduct an electric current.

15. Electrolytes vs. Nonelectrolytes
The ammeter measures the flow of electrons (current)
through the circuit.
If the ammeter measures a current, and the bulb
glows, then the solution conducts.
If the ammeter fails to measure a current, and the
bulb does not glow, the solution is non-conducting.

16. Try to classify the following substances as electrolytes or nonelectrolytes…
Pure water
Tap water
Sugar solution
Sodium chloride solution
Hydrochloric acid solution
Lactic acid solution
Ethyl alcohol solution
Pure sodium chloride

17. Answers to Electrolytes
NONELECTROLYTES:
Tap water (weak)
NaCl solution
HCl solution
Lactate solution (weak)
Pure water
Sugar solution
Ethanol solution
Pure NaCl

18. Colligative Properties
Colligative properties are those that depend on the concentration of particles in a solution, not upon the identity of those particles.
Boiling Point Elevation
Freezing Point Depression
Osmotic Pressure

19. Freezing Point Depression
Each mole of solute particles lowers the freezing point of 1 kilogram of water by 1.86 degrees Celsius.
Boiling Point Elevation
Each mole of nonvolatile solute particles raises the boiling point of 1 kilogram of water by 0.51 degrees Celsius.

20. Calculations of Solution Concentration

21. Ga Standards Students know the definitions of solute and solvent.
Students know how to calculate the concentration of a solute in terms of molarity, prepare a properly labeled solution, and how to apply the concept of molality.

22. Calculations of Solution Concentration: Molarity
Molarity is the ratio of moles of solute to liters of solution

23. A Simplifying Assumption
1 ml of water = 1 gram of water
1000 ml of water = 1 liter = 1000 grams
Assume that solutions with water as the solvent have the density of pure water (1 mL = 1 gram)
It’s not true, but it’s close enough 