1. Water- Essential for Life

2. The Blue Planet Oceans cover nearly 71% of Earth’s surface,
most obvious feature of Earth as seen from space.

4. Fresh water- page 268 Fresh Water Type Location Amount Frozen Water
Poles, Glaciers, Winter
Ground Water
Found in aquifers, underground rivers, in porous rock
Surface water
Ponds, Lakes, rivers
Vapour
Atmosphere

6. States of Water- Density

7. Hydrogen bonding (electric attraction)
Ice
Liquid

8. Water- Surface Tension

9. Water: the universal solvent
Solutions in which water is the solvent are called aqueous solutions
Polar molecule
Oxygen atom has a partial negative charge
Hydrogen atoms have a partial positive charge

10. Dissolution of Solid Solute
What are the driving forces which cause solutes to dissolve to form solutions?
1. Covalent solutes dissolve by attraction between polar ends and solvent’s poles
2. Ionic solutes dissolve by dissociation into their ions.

11. Solution Animation

12. Solution Process - Ionic Compounds
Attractive forces between anions & cations in solid
versus
Attractive forces between water molecules and cations & water and anions

13. The Solution Process Molecular Compounds
Covalent molecules that are small and have “polar” groups tend to be soluble in water 4

14. Likes dissolve likes
Molecules that are similar in structure tend to form solutions
Which of these molecules will dissolve in water?

15. Ionic Solutions How do we know ions are present in aqueous solutions?
The solutions _________________________
They are called ELECTROLYTES
HCl, MgCl2, and NaCl are strong electrolytes.
They dissociate completely
(or nearly so) into ions.

16. Molecular Solutions
Some compounds dissolve in water but do not conduct electricity. They are called nonelectrolytes.
Examples include:
sugar
ethanol
ethylene glycol

17. Electrolytes in the Body
Carry messages to and from the brain as electrical signals
Maintain cellular function with the correct concentrations electrolytes

18. Definitions Solutions can be classified as saturated or unsaturated.
A saturated solution contains the maximum quantity of solute that dissolves at that temperature.
An unsaturated solution contains less than the maximum amount of solute that can dissolve at a particular temperature

19. Supersaturated Solutions
Under some conditions, more solute will dissolve than “saturated”. Heat most salts in water, the solubility increases. Slowly cool down the solution. Extra solid doesn’t come out easily. Something happens to cause crystals to form. Then, zap, they form.
Examples: fudge, honey

20. Supersaturated Sodium Acetate
One application of a supersaturated solution is the sodium acetate “heat pack.”

21. Homework
Page 274
1,2, 4a), 5, 6