1. Bell Work 1. What does it mean to be suspended in something? 2. What is a mixture? 3. What is the formula for molarity? If you are not sure, look it up in the Stoichiometry notes. 4. What is a solvent? How about a solute? 5. What do you think a part per million is? 6. What does the word saturated mean? 7. What does it mean to be soluble? 8. What do the prefixes un- and super- mean? 9. What can we do to make things dissolve faster? 10. What do you think happens to the solubility of gases when you increase temperature? What about an increase of pressure?

2. Reality Check ½ piece of paper Don’t forget the back side!!! Also, don’t forget to turn in Bell Work!!!

3. Solutions

4. Key Terms A mixture that is the same throughout A mixture that is not the same throughout Another name for a homogenous mixture A mixture in which the particles spontaneously separate over time Homogeneous Mixture Suspension Solution Heterogeneous Mixture

5. More Key Terms In a solution, the substance that dissolves the other substance In a solution, the substance that is dissolved Most common solvent Solutions in which water is the solvent Solvent Solute Water Aqueous

6. A few more Key Terms A stable heterogeneous mixture. It is made up of tiny particles, that are too big to make it a solution, but too small to separate. Most have a _________ that keeps them from making bigger particles that would settle out. Example: Colloid Charge Milk

7. Comparing the Mixture Types Particle Size? See Through? Settle Out? Tyndall Effect? Solutions Suspensions Colloids Small Large Medium Yes No Yes No Tyndall Effect – the phenomenon in which light is scattered by very small particles in its path.

8. Dissolving Process Polarity –The polarity of the solute and solvent has a great impact on whether they will dissolve –Like dissolves like (polar dissolves polar) –Miscible – two or more liquids that are able to dissolve into each other in various proportions. –Immiscible – two or more liquids that do not mix with each other.

9. How to dissolve immiscible liquids A compound that concentrates at the boundary surface between two immiscible phases. It has a polar end and a nonpolar end. Example is a Any mixture of two or more immiscible liquids in which one liquid is dispensed in the other. Surfactant detergent Emulsion

10. Dissolving Process Surface area –Larger the surface area, the faster the solute will dissolve (lots of small pieces will dissolve faster than 1 big piece) Agitation (stirring) increases the rate of dissolving Temperature –Temperature affects solubility –For solids and liquids, increase temperature = increase in solubility –When gases are involved, an increase in temperature = decrease in solubility.

11. Solubility can be determined by a Solubility Graph

12. Saturation A solution that cannot dissolve any more solute under the current conditions. A solution that contains less solute than a saturated solution and is able to dissolve additional solute. A solution that contains more solute than what is required to reach equilibrium at a given temperature Saturated solution Unsaturated solution Supersaturated solution

13. Henry’s Law The law that states that at constant temperature, the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas on the surface of the liquid. In other words, the higher the pressure of the gas, the higher its solubility. Brownian Motion The random movement of microscopic particles suspended in a fluid.

14. Concentration Equations Molarity –Moles solute per liter solution, so M=mol/L –Special Molarity formula for dilution problems: M 1 V 1 =M 2 V 2 Molality –Moles solute per kg solvent, so m=mol/kg Parts per million –g solute per 1,000,000 g solution, so ppm = mass (grams)/mass (grams) x 1000000

15. Examples 5.85 grams of NaCl are added to enough water to make 500 mL of solution. What is the molarity of the solution? You need to make 500 mL of 3.0 M HCl. How much 12.0 M HCl would you need?

16. Examples 30.0 grams of zinc is dissolved into 440 grams of gold. What is its molality? Helium gas, 3.0 x 10 -4 g, is dissolved in 200.0 g of water. Express this concentration in parts per million.

17. Homework Worksheet

18. Today’s Lab You will have to boil a large amount of water for this crystal formation lab. So, fill up the beaker with tap water and start heating it. While you wait, use 1 or 2 pipe cleaners to make a small shape that can be suspended in a cup with room on the top and bottom.