1. Water and Solutions Chapter 6.3 pgs. 161-165

2. Why is water so important??

3. Water molecule: H2O
Covalent bonds hold a single water molecule together.
The electrons are pulled towards the bond.
This leaves one side slightly more positive than the other.
This makes water POLAR!

4. The Polarity of Water Creates Hydrogen Bonds with other water molecules, giving it its properties.

5. Extraordinary Properties of Water
1. Adhesion
Water molecules cling to other surfaces.
Example: Capillary action, as in water moving up a plant stem

6. 2. Cohesion Water molecules stick together
- this creates Surface Tension

8. 3. Water is less dense as a solid!
This allows for aquatic life to live under the ice in the extreme cold.

9. Why ice really does float:

10. 4. Water is a good solvent
Solvent = a substance in which another substance is dissolved in
Solute = a substance dissolved in a solvent
Solution = when a solvent and solute are combined

11. pH scales measure if a solution is an ACID OR BASE
The scale goes from values 0 through 14.

12. Bases Acids pH between 0 and 6.9 on the pH scale Taste sour
Corrode metals (acid rain)
Bases
pH between 7.1 and 14 on the pH scale
Taste bitter, chalky
Feel soapy, slippery

13. ACID BASE
H+ = hydronium ion OH- = hydroxide ion

14. Buffer Neutral pH number is 7 Examples: blood, water
Solutions that keep the pH within a particular pH range.
Buffered aspirin has a coting on it to
Keep the acid in your stomach from
dissolving it right away.