A homogeneous mixture Example: ________________ Solution = solute + solvent Characteristics: 1) 2) 3) Solubility: ______________________________________ Calculate solubility_______________________________________ Grams of solute / 100 g (ml) of water for a saturated solution at a certain temperature. Use proportions g = x g ml 100 ml NaCl (aq) Clear (not cloudy) but may be colored Will not settle out Goes through filter paper to recover salt, evaporate Salts or what is dissolved Water or other solvent SATURATED_______________________________ _____ no more will dissolve

Example: What is the solubility if 22 grams of NaCl dissolve in 30 ml of water? 22 g = X 30 ml 100ml X = 73.3 g/100 ml H 2 O Add vocab dilute, concentrated, and others from solutions worksheet

Types of solutions: 1) liquid / liquid _________________ 2) solid / liquid __________________ 3) gas / liquid ___________________ 4) solid / solid ___________________ 5) gas / gas ______________________ Alcohol in water Salts in water Soda is “carbonated” CO 2 is dissolved in water. Alloys: Zn in Cu = brass Air is O 2 In N 2 (78%)

Factors affecting solubility 1)Temperature_____________________________ 2)Nature of substances _____________________ 3)Pressure _______________________________ Factors that affect the Rate of dissolving 1)________________ 3) __________________ 2)________________ 4) __________________ temp solubility for solids temp solubility for gases, the OPPOSITE! “like dissolves like” polar mixes with polar, np w/ np Affects gases only, pressure, ↑ solubility Stir/ shake Powder it ( ↑ surface area ) Amount already dissolvedHigher temp Keep fizz in your soda, low temp, high pressure IONIC SALTS ARE POLAR

Reference Table G Solubility of substances at various temperatures Saturated ___________________________ Unsaturated _________________________ Supersaturated_______________________ X Y Z If a problem is NOT using 100 ml of water: Use proportions Comparing solubility on Table G The _________ the line, the ____________ soluble The _________ the line, the ____________ soluble. Substances with equal solubility at a given temp ___________ X on the line Z below the lines Y above the line lower less higher more intersect

Reference Table F Solubility Guidelines Which of the following substances are soluble? Mark “s” for soluble, “i” for insoluble 1)NaBr _____ 3) AgCl _____ 5) Mg(OH) 2 _____ 7)CaSO 4 _____ 2)NH 4 F _____ 4) BaS _____ 6) PbSO 4 ______ 8) AlPO 3 ______ s s i i i i i i

Review: Double replacement reactions: Pb(NO 3 ) 2 + KI  KNO 3 + PbI 2 What is the precipitate? ____________ PbI 2 Soluble compounds stay dissolved, insoluble products form precipitates

Practical Applications 1.Why do fish die in warm water? ____________________ 2.What is the carbonation in soda? How do you keep the fizz in your soda? 3. How can you make a saturated solution, unsaturated? 4. How can you make an unsaturated solution, saturated? 5. What is the universal solvent?___________

Why do fish die in warm H 2 O? Fish need to breathe dissolved O 2 (through their gills), which dissolves better in cold H 2 O.

MOLARITY (M) = moles of solute liter of solution Salt (NaCl) = 58 g / mole 1 M solution contains _____ g in _________ml of H 2 O 2 M solution contains _____ g in _________ ml of H 2 O.5 M solution contains _____ g in _________ mol of H 2 O What is the molarity of a solution in which 87 g of NaCl is dissolved in 500 ml of H 2 O? Reference Table includes ppm (parts per million) and % by mass or % by volume g = 87 g = 1.5 mol M = moles liters M = 1.5 mol = 3M.5L 1 mol X mol On Ref Table

MOLARITY (M) = moles of solute liter of solution Salt (NaCl) = 58 g / mole 1 M solution contains _____ g in _________ml of H 2 O 2 M solution contains _____ g in _________ ml of H 2 O.5 M solution contains _____ g in _________ mol of H 2 O What is the molarity of a solution in which 87 g of NaCl is dissolved in 500 ml of H 2 O? Reference Table includes ppm (parts per million) and % by mass or % by volume g 1 mol = 1.5 mol 58 g M = moles liters M = 1.5 mol = 3M.5L

All Formulas are on the back of the Reference Tables 1)Molarity (M) = Dissolve 25 grams of CuCl 2 in 2000 ml of water. Find the molarity of the solution. 2 ) % Concentration by Mass = Example: same problem as in #1 but % concentration by mass. moles =135g/mol 135 g = 25 g =.19 mol M =.19 2 L liter.09 M 25 g x 100 = 2025 g 1.2% whole part x mol X mol

All Formulas are on the back of the Reference Tables 1)Molarity (M) = Dissolve 25 grams of CuCl 2 in 2000 ml of water. Find the molarity of the solution. 2 ) % Concentration by Mass = Example: same problem as in #1 but % concentration by mass. moles =135g/mol 25 g 1 mol =.19 mol 135 g M =.19 2 L liter.09 M 25 g x 100 = 2025 g 1.2% whole part x 100

3) % Concentration by Volume = Example: What is the % concentration by volume if 30. ml of ethanol is added to 80. ml of water? 4) Parts per Million (ppm) = Example: What is the concentration in parts per million if.0035 grams of oxygen is dissolved in 50. ml of water? “whole” in solutions must include the solute & solvent if it’s not given together!! Very dilute solutions 30 ml x 100 = 27 % = 110 ml part x 100 whole part x 1,000,000 whole.0035 x 1,000, ppm

5) Dilutions M V = M V (use titration formula) Example: 200. ml of a 3 M solution is diluted to 500. ml What is its concentration? (in molarity) 200 ml (3 M) = 500 ml (X) 1.2 M Concentrated: a solution that contains a large amount of solute Dilution/diluted: the process of reducing the concentration of a solute in solution, usually simply by mixing with more solvent. Example: You can add water to concentrated orange juice to dilute it until it reaches a concentration that is pleasant to drink.

Define:Properties of solutions that depend on the # of dissolved particles Properties that change: 1) _____________2)____________ 3) ___________ vapor pressureboiling ptsfreezing pts solvent molecule solute molecule more vapor (higher v.p.) pure liquid solution less vapor (lower v.p.) freezing in pure water vs solution

Vapor pressure: adding solute, v.p. Boiling point elevation. Adding solute, raises b.p. by.52 0 C / mole Freezing point depression. Adding solute lowers f.p. by C / mole Salt interrupts crystal formation must get colder to freeze C 0 0 C

NUMBERS OF PARTICLES One particle: A covalently bonded substance (2 or more nonmetals) made up of molecules such as sugar, C 6 H 12 O 6 in water. They are nonelectrolytes (solutions that do not conduct electricity) More than one particle: Salts which are ionic bonds (metal + nonmetal or polyatomic ion) disassociate in water. Acids also disassociate in water. These solutions do conduct electricity due to charges that can move & are electrolytes EXAMPLES NaCl  Na + + Cl -- (2 particles) Al 2 (SO 4 ) 3  2 Al SO 4 -2 (5 particles) How many particles: Ca(OH) 2 ______ Sr(NO 3 ) 2 _______ MgCl 2 _______ C 12 O 22 H 12 ________ H 2 SO 4 ________ C 3 H 8 ________

Practical Applications Salt lowers freezing point on icy roads (by interrupting the ice crystal formation, it has to get colder to freeze salt water) Salt in pasta water, makes it boil hotter and cook the pasta faster. (salt lowers the vapor pressure which directly affects the boiling point.)

Concentrations: Percent by Mass (%) Parts per Million (ppm) 1. What is the percent by mass of a solution that contains 50. grams of solute dissolved in 200. grams of solution? What is the concentration of the same solution in parts per million? 2. What is the percent by mass of a solution that contains 75 grams of salt dissolved in 150. Grams of water? What is the concentration of the same solution in parts per million?

3. If a solution is 25.0% NaCl by mass, what is the mass of salt contained in 150. grams of the solution? 4. What mass of solute is needed to prepare 500. grams of a 15.0% by mass solution? 5. What mass of sugar is present in 2.50 kilograms of solution that is 30.0% by mass? 6. What is the mass of solute present in 250. Grams of a solution that is 12.0% by mass? ml of a 6.0 M solution is diluted to a new volume of ml. What is the new concentration in molarity?

8. Our atmosphere contains approximately 21% oxygen. What is this concentration expressed in ppm? 9. Fish need oxygen concentrations of approximately 6.0 ppm in order to survive in the water. What is this concentration expressed in percent by mass? 10. What is the concentration expressed in percent by mass when 0.5 moles of NaOH is dissolved in 200. Grams of water? What is the concentration of the same solution in parts per million?

11. What sis the concentration of a solution which contains 6.0 moles of HCl dissolved in 500. Grams of water? What is the concentration of the same solution in parts per million? 12. What mass of copper sulfate is needed to prepare 2.5 kilograms of a solution that is 25.0% by mass 13. What is the percent by volume of a solution in which 50. ml of ethanol is dissolved in 300. ml of water? 14. If isopropyl alcohol is 70% alcohol by volume, how much of the solution is plain water in a bottle containing 500. ml

NH 3 HCl SO 2 Decreasing solubility with hotter temp (lines slope down) 33 g 60 g 30 g 48 g

NH 4 Cl KNO 3 NaCl On the lines Below the lines

unsaturated supersaturated 105 g 30 g 400 g supersaturated 60 g = x 100 g 50 g 80 g = x 100 g 500 g

NaNO 3 or KNO 3 not KI because it is off the chart SO 2 78 g 135 – 78 = 57 g 20 g KI KClO 3

CALCULATIONS 1.Find the mass of the copper produced (c-a) 2.Calculate the number of moles of copper produced 3.Find the number of moles of iron reacted. 4.Find the whole number ratio of moles of iron to moles of copper Lab 29 Fe + CuSO 4