1. Aim: What factors affect solubility? DO Now: Take out your homework. In pairs discuss and explain your answers.

2. Solubility Factors The following have an effect on how much of something can be dissolved- Nature of the solute and solvent Temperature Pressure (gases)

3. “Like Dissolves Like” In chemistry the phrase is used to describe how solutes and solvents will interact with each other. I 2 solid CCl 4 liquid Both nonpolar ethanol water Both polar In Both cases the substances are soluble

4. Nature of the Substances SoluteType Non Polar Solvent PolarSolvent NonpolarSolubleInsoluble PolarInsolubleSoluble IonicInsolubleSoluble

5. Temperature For most solids solubility in water increases with an increase in temperature. Ex: dissolving sugar in tea For gases the opposite is true; solubility in a liquid decreases with an increase with temperature. Why? Increasing temp allows the gases to escape the liquid.

6. Pressure Pressure has little no affect on the solubility of solids or liquids Pressure affects solubility of a gas in a liquid. As pressure increases, the solubility of a gas increases. Ex: Opening up a soda can.

7. Solubility Factors The following will effect how fast something dissolves- Particle size Stirring

8. Particle Size The rate at which a solute dissolves depends on the particle size of the solute. The bigger the particle the longer it takes to dissolve it.

9. Stirring Stirring increases the rate at which a solute dissolves because during stirring the fresh solvent is continuously in contact with the solute.

10. Question 1 Describe two methods by which you could remove gases that are dissolved in water.

11. Question 2 Which process or processes affect the speed of dissolving? 1. Particle size, temperature and stirring 2. Particle size and stirring only 3. Stirring only 4. Particle size only

12. Question 3 You are given an aqueous solution of sodium chloride that is saturated and has crystals of sodium chloride floating in it. What will happen to the sodium chloride crystals as you raise the temperature? 1. they will begin to boil 2. they will grow as sodium chloride precipitates out 3. they will begin to dissolve 4. they will stay the same size

13. Question 4 As you cool a solution of a gas in water, what happens to the solubility of the gas? 1. it goes down 2. it goes up 3. it depends on the gas 4. it stays the same