1. Water Unit B: A Look at Water and It’s Contaminants

2. Physical Properties of Water (B.1)
Every substance has a set of unique physical and chemical properties that allows it to be differentiated (isolated) from ALL other substances

3. Physical Property
A characteristic of a substance that is observable without changing what it is (color, odor, physical state, boiling/freezing points, etc..)

4. Chemical Properties
A characteristic of a substance that describes how it interacts with other substances (solubility, flammability, reacts w/ acids and bases)

5. Physical/Chemical Change
Physical Change: Does not change the what the substance is (i.e. state change, sample size, etc.)
Chemical Change: Original substance changes to another substance with different physical and chemical properties (shown by a change in temp, smell, color, gas formation, etc..)

6. Physical Properties of Water
Colorless
Odorless
Tasteless
Unusually high boiling point (100° C)
Low Freezing Point (0° C)
Unusually High Surface Tension
Density of solid form LESS than liquid form

7. UNUSUAL PROPERTIES OF WATER
High SURFACE TENSION
High BOILING POINT 100oC
Low FREEZING POINT 0oC

8. Density
D=M/V
How much mass in a certain volume

9. Mixtures and Solutions (B.2)
Mixture: when two things are combined and retain their individual properties, large particles
Example: bird seed mixtures

10. Terms Heterogeneous: not completely uniform throughout
Oil and water
Homogeneous: Uniform throughout
Colored Water

11. Terms (Cont) Solute: The substance being dissolved
Solvent: the dissolving agent

12. Solutions Solution: Smallest solute particles Aqueous Solution: a
NaCl + H20
Aqueous Solution: a
solution in water
Salt water is aqueous
NaCl (aq)

13. Colloids
Colloids: bridge the gap between solutions and suspensions, the particles are dispersed without bonding to solvent molecules, and they do not settle out on standing.

14. Solution Vs Mixture Mixture Solution Larger particle size
Small particle size
does not separate on standing
entire solution will pass through the filter
mixture appears clear rather than cloudy
solute is completely dissolved into the solvent
solution shows an increase in boiling point/melting point
Mixture
Larger particle size
Can/will separate on standing
Can separate by filtering
Can appear cloudy
Solute is not dissolved in solvent

15. WATER POLARITY

16. ATOMS VS. MOLECULES

17. DIATOMIC MOLECULES – AKA Mr. BrINClHOF

18. Crystalline structure of Ionic compounds
How do they dissolve?

24. Density Test Material Density (g/ml) Float? Cork 0.24 Aluminum 2.70
Iron
7.86
Carbon Dioxide
0.0018
Gasoline
0.67
Water
1.00

25. Tyndall effect
Property of a mixture which allows observer to see beam of light passing through mixture