Bell Ringer 11-23-09 Get our your yellow foldable from the other day. We are going to complete the 4th box that is empty. Write Heterogeneous and Homogenous Mixtures on the front cover of the flap.

Concentration and Solubility Chapter 7 Section 2 Concentration and Solubility

Concentration = the amount of solute dissolved in a certain amount of solvent

Does maple syrup really come from sap? Why is sap not as sweet as maple syrup?

Dilute solution- a mixture that has only a little solute dissolved in a certain amount of solvent (sap) Concentrated solution- a mixture that has a lot of solute dissolved in the same amount of solvent (maple syrup)

Changing concentration You can change concentration by adding more solute or removing _____. To measure concentration, you compare the amt. of solute to the amount of ____.

Solubility Solubility is a measure of how much solute can dissolve in a solvent at a given temperature. A saturated solution contains so much solute that no more dissolves. An unsaturated solution can continue to dissolve more solute.

Solubility can be used to help identify a substance because it is a characteristic property of matter.

Factors Affecting Solubility Pressure Type of Solvent Temperature

1. Pressure – the higher the pressure of the gas over the solvent , the more gas can dissolve Examples: CO2 gas is added to soft drinks under high pressure The bends…when N2 comes out of solution in the blood if diver tries to come up too quickly

2. Solvents – “ like dissolves like”… polar will dissolve in polar nonpolar will dissolve in nonpolar Examples: Water-based (latex) paints can be cleaned up with soap and water Oil-based paints need a nonpolar solvent such as turpentine.

3. Temperature – For most solids, solubility increases as the temperature increases. BUT, gases become less soluble when the temperature goes up.

Activity Clear your desk of EVERYTYHING except a pen/ pencil and your science notebook. We are going to complete the lab we started last Thursday.

Activity Clear your desk of EVERYTYHING except a pen/ pencil and your science notebook. Copy the list of mixtures from side board skipping two lines in between each one. Partners

Is it a solution, colloid, or a suspension? - Why? Is it heterogeneous or homogeneous?