12Water is an excellent solvent. It is the “universal solvent.” Solutions made with water are called aqueous solutions.
13Factors that affect rate of solvation Stirring the mixtureIncreasing the surface area of the soluteIncreasing the temperature of the solventIncreasing the pressure when dissolving a gas
14Solubility = maximum amount of solute that will dissolve in a given amount of solvent at a specified temperature and pressureSaturated = maximum amount of solute is dissolvedUnsaturated = more solute can be dissolvedSupersaturated = contains more dissolved solute than a saturated solution at the same temperature.
16Factors that affect solubility Increased Temperature – solubility of solids increases; solubility of gases decreases.Increased Pressure – solubility of gases increases. (This process is called aeration)
17Ch.15.2- Solution Concentration The concentration of a solution is a measure of how much solute is dissolved in a specific amount of solvent or solution.solute or solutesolvent solution(solution = solute + solvent)
18Expressing Concentration Concentration may be described qualitatively as concentrated or dilute.
19Concentration= solute or solute solvent solution
20Percent by Mass (p.463 #8)What is the percent by mass of NaHCO3 in a solution containing 20 g NaHCO3 dissolved in 600 mL H2O?Density of H2O = 1.00 g/mL% by mass = g x 100 = 3.2%620 g
21Percent by Mass (p.463 #9)You have g of a bleach solution. The percent by mass of the solute sodium hypochlorite, NaOCl, is 3.62%. How many grams of NaOCl are in the solution?% Mass = mass solute x 100mass solution3.62 = x g X 100gx = 54.3 g NaOCl
22Percent by Volume (p.464 #12)If you have mL of a 30.0% aqueous solution of ethanol, what volumes of ethanol and water are in the solution?% Volume = volume of solute x 100%volume of solution30.0 % = x mL x 100100.0 mLx = 30 mL ethanol70 mL water
23Molarity (p.465 #14)What is the molarity of an aqueous solution containing 40.0 g of glucose (C6H12O6) in 1.5 L of solution?1 mole C6H12O6 = g40.0 g C6H12O6 x 1 mole = molgMolarity = mol = M C6H12O61.5 liter
24Molarity (p.465 #15)What is the molarity of a bleach solution containing 9.5 g NaOCl per liter of bleach?
25Molarity (p.465 #16)Calculate the molarity of 1.60 L of a solution containing 1.55 g of dissolved KBr.
26Molarity (p.466 #17)How many grams of CaCl2 would be dissolved in 1.0 L of a 0.10 M solution of CaCl2?
28Diluting Solutions- p.467In the laboratory, you may use concentrated solutions called stock solutions.For example, concentrated hydrochloric acid (HCl) is 12 M.You can dilute the stock solution by adding more solvent.Would you still have the same number of moles of solute particles that were in the stock solution?
29moles solute in stock solution = moles solute after dilution Diluting Solutions- p.467Molarity (M) = moles soluteliters solutionmoles solute = Molarity x liters solutionBecause the total number of moles of solute does not change during dilution,moles solute in stock solution = moles solute after dilutionM1V1 = M2V2
30Diluting Solutions- p.468 #21 What volume of a 3.00 M KI stock solution would you use to make L of a 1.25 M KI solution?
31Diluting Solutions- p.468 #23 If you dilute 20.0 mL of a 3.5 M solution to make mL of solution, what is the molarity of the dilute solution?
32Molality- p.469 Molality (m) = moles solute = moles solute kilogram solvent g solventWhat is the molality of a solution containing g Na2SO4 dissolved in g of water?What is the molality of a solution containing 30.0 g of naphthalene dissolved in 500.0g of toluene?