1. Chapter 3 Section 3:“Mixtures” Notes 12/4/07

2. I. Properties of Mixtures: A. A combination of two or more substances that are not chemically combined (they do not react to form a compound). B. When a mixture is made there is no chemical change. Each substance in a mixture keeps its identity (some you can see the components of the mixture).

3. C. Substances in a mixture can be separated w/out changing their identities. 1.Ways to separate mixtures: a.Distillation – separates components based on their boiling points b. Magnet – separates some metals in a mixture c. Centrifuge – separates components based on their densities

4. d. Filter – separates components based on their size

5. II. Solutions: A. An even distribution of 2 or more substances’ particles in a mixture is called a solution. B. In a solution the solute is the substance that has dissolved. The solute has dissolved into the solvent. The solute must be soluble (dissolve) in the solvent.

6. C. Solutions can be a mixture of any states of matter. D. The particles in a solution never settle out, do not scatter light, and cannot be filtered out.

7. III. Concentration of Solutions: A.The amount of solute dissolved in a solvent = concentration of solution (solute in g / solvent in ml). 1.What is the concentration of solution if it has 55g of sugar (solute) dissolved in 500 ml of water (solvent)? Solute 55g Concentration = ___________ = _________ = 0.11 g/ml Solvent 500ml

8. B. The dilute solution contains less solute than a concentrated solution, both have the same amount of solvent. C. A solute at a given temperature will only dissolve so much in a solvent. This is the solutes solubility.

9. D. Three ways to make solids dissolve faster in liquids are: Mixing – cause particles to spread out quicker Heating – causes particles to move quicker Crushing – makes particles smaller E. Solids are more soluble in liquids at higher temperatures, while gases become less soluble in warmer temperatures.

10. V. Suspensions: A. A mixture where particles of a material are too large to stay mixed, they settle out, unless the mixture is stirred or shaken.

11. VI. Colloids: Mixture that has properties between those of solutions and suspensions. The particles are not large enough settle out, but are large enough to scatter light. Examples: Milk, Jell-O, whipped cream, and mayonnaise.