1. Solutions!

2. Classification of Matter Matter Pure Substanc es Mixtures HomogeneousMixturesHeterogeneousMixturesElementsCompounds

3. Heterogeneous Mixtures See visibly different regionsSee visibly different regions –Granite –Dirt –Cereals –Oil & Vinegar See a boundarySee a boundary –Ice cube in water

4. Homogeneous Mixtures Particles very small – on atomic scaleParticles very small – on atomic scale –Can’t see particles –Can’t sort particles –Can’t get trapped by filter –Can’t scatter light Particles evenly distributedParticles evenly distributed Particles do not separateParticles do not separate

5. Solution Homogeneous mixture of 2 or more substances in a single physical state (phase)

6. Parts of a Solution SoluteSolute = substance being dissolved SolventSolvent = dispersing medium that substance is being dissolved in

7. Identify the solute and solvent in each picture

8. Solute = ? Solvent = ?

9. Hints to identify solute & solvent SoluteSolute: –substance that changes phase –substance that have less of SolvenSolvent: –substance that maintains phase –substance that have more of

10. Aqueous Solutions WaterWater is solvent Transition metalsTransition metals form brightly colored solutions

11. Solutions occur in all 3 phases! Alloys: Brass, etc. SolidSolid Fillings: Hg in Ag SolidLiquid H 2 in Pd metal SolidGas Salt water LiquidSolid Antifreeze in radiator LiquidLiquid Seltzer Water LiquidGas MothballsGasSolid Water Vapor in Air GasLiquid AirGasGas ExampleSolventSolute

12. Gas in a liquid: CO 2 in and out of water Bubbles mean it ’ s a mixture not a solution!

13. Concentration of Solutions

14. Concentration measurement that describesmeasurement that describes how much solute in given amount of how much solute in given amount of solvent or solution solvent or solution express concentration using many, many different unitsexpress concentration using many, many different units –pick the unit according to task at hand

15. Percent By mass By Volume % = Part x 100 Whole

16. Twists sometimes ask for part or whole, not percent sometimes give volume/mass of solution sometimes give volume/mass of solvent and volume/mass of solute Mass solution = Mass solute + Mass solvent

18. ppm (parts per million) used when solute is present in very small amountsused when solute is present in very small amounts (Regents board doesn’t follow this rule) (Regents board doesn’t follow this rule)

19. ppm (parts per million) ppm = grams solute x 1,000,000 ppm is ratio between mass solute & mass soln like % except you multiply by 1,000,000 instead of 100 grams solution

20. About 0.0043 g of O 2 can be dissolved in 100 mL of water at 20 o C. Express in ppm. [Memorize: 1 mL water has mass of 1 g] ppm = 0.0043g x 1,000,000 100.0043 = 43 ppm

21. CO 2 gas has solubility of 0.0972 g/100 g water at 40 o C. Express in parts per million. ppm = 0.0972 g solute x 1,000,000 100.0972 g solution = 971 ppm

22. What is the concentration in ppm of a solution with 30.0 g NaNO 3 in 70.0 g water? ppm = 30.0 g NaNO 3 x 1,000,000 100.0 g solution = 300,000 = 3.0 X 10 5 ppm

23. How many grams of KOH are needed to be dissolved in water to make 2000.0 grams of a 10.0 ppm solution? 10 ppm = ? grams KOH X 1,000,000 2000.0 g solution ? = 0.02 grams KOH