1. Chapter 4 Notes
Mixtures
& Solutions

2. (uniform composition) (variable composition)
Matter
Pure Substance
(uniform composition)
Mixture
(variable composition)
Elements
(only one
kind
of atom)
Compounds
(atoms in
consistent
proportions)
Homo-
geneous
(uniform
distribution)
Hetero-
geneous
(non-uniform
distibution)

4. MIXTURE BASICS
Mixtures are usually how you find things in nature. Rocks, the ocean, just about anything you find.
They are substances held together by PHYSICAL FORCES, not chemical.

5. Properties of Mixtures
Substances do not chemically combined
Substances may change in physical appearance (but not chemical comp.)
Substances can be present in any amount

6. Tap water is a mixture of water with other dissolved substances
Tap water is a mixture of water with other dissolved substances. Distilled water is a pure substance.

7. MIXTURES: a physical blend of two or more pure substances
Homogeneous A mixture with a completely uniform distribution. Only one phase of matter is apparent. Heterogeneous A mixture of variable, non-uniform distribution. Two visible phases of matter present.

8. Appear to be the same throughout
Examples:
Glass
Air
Metal
Homogeneous Mixtures
Appear to be the same throughout
Do not separate out

9. Heterogeneous Mixtures Separate & settle out easily
Examples:
Oil & vinegar
Sand in water
Granite
Heterogeneous Mixtures
Separate & settle out easily

10. Colloids a homogeneous mixture
Particles are mixed but not dissolved
Particles are kept suspended
Cloudy appearance b/c particles are hitting each & keeping them from settling out
Examples = milk, toothpaste, whipped cream

11. Solutions type of homogeneous mixture of 2 or more substances in a single physical state
Best mixed of all the mixtures
Examples = salt water, air, antifreeze, powdered Tang, tea, or lemonade in water
One substance that dissolves = the SOLUTE
One substance that does the dissolving = the SOLVENT

12. Properties of Solutions
Universal solvent = water
Particles are small
Particles cannot be separated by simple physical means
Every part of a solution tastes the same
Thus, particles are evenly distributed (spread out)

13. SOLUTIONS: homogeneous mixtures
solid in solid (sand)
solid in liquid (muddy water or blood)
solid in gas (smoke)
liquid in liquid (oil in water)
liquid in gas (air freshener)
gas in liquid (bubbles)
gas in gas (air)

14. Solubility Soluble = a substance that dissolves
Insoluble = a substance that does not dissolve
The ability of the solvent to dissolve the solute at a specific temperature = solubility
Increase temperature  increase solubility

15. Compare the following:

17. Pure elements
Elements made of single atoms
An element made of molecules
Mixture of two elements
Mixture of three elements
Pure compounds
Mixture of two compounds