Ch 13Ch 13

SolutionsSolutions

SolutionsSolutions

Solution: homogeneous mixture of Solution: homogeneous mixture of two substances. Each substance two substances. Each substance retains its identity.retains its identity.

Solvent: component of a solution Solvent: component of a solution present in larger amount.present in larger amount.

Solute: component of a solution Solute: component of a solution present in smaller amount.present in smaller amount.

SolubilitySolubility

Maximum amount of solute that will Maximum amount of solute that will dissolve in a given solvent.dissolve in a given solvent.

Effect on solubilityEffect on solubility

1.1. Effect of temperature: solids are more Effect of temperature: solids are more soluble in water with an increase in soluble in water with an increase in temp.temp.

Units: g solute/100 g solventUnits: g solute/100 g solvent Less than 0.1-insoluble.Less than 0.1-insoluble. 0.1-1-slightly soluble.0.1-1-slightly soluble. 1-10-soluble.1-10-soluble. Greater than 10-very soluble.Greater than 10-very soluble.

Effect on solubilityEffect on solubility

2. Effect of pressure: Does not affect 2. Effect of pressure: Does not affect solbility of solids, liquids.But affects solbility of solids, liquids.But affects the solubility of gases. As pressure the solubility of gases. As pressure increases solubility increases.increases solubility increases.

Effect on solubilityEffect on solubility

3.Amount of solute in a solution: 3.Amount of solute in a solution: Saturated solution: A solution that Saturated solution: A solution that

contains maximum amount of solute contains maximum amount of solute that can be dissolved.that can be dissolved.

Unsaturated solution: A solution that Unsaturated solution: A solution that contains less solute than maximum contains less solute than maximum amount that can be dissolved.amount that can be dissolved.

Superstaurated: A solution that Superstaurated: A solution that contains more dissolved solute than contains more dissolved solute than that needed for a saturated solution.that needed for a saturated solution.

3.Amount of solute in a 3.Amount of solute in a solution:solution:

Dilute solution: contains small amount Dilute solution: contains small amount of solute relative to the amount that of solute relative to the amount that could dissolve.could dissolve.

Concentrated solution: contains large Concentrated solution: contains large amount of solute relative to the amount amount of solute relative to the amount that could dissolve.that could dissolve.

Aqueous solution: solution in which Aqueous solution: solution in which water is a solvent.water is a solvent.

Nonaqueous solution: A substance other Nonaqueous solution: A substance other than water is a solvent.than water is a solvent.

Solution FormationSolution Formation

Factors affecting rate of solution Factors affecting rate of solution formation: formation:

size of the particles- smaller the size of the particles- smaller the size , larger the surface area.size , larger the surface area.

Stirring- increases interactions.Stirring- increases interactions. Temperature (increase)- increases Temperature (increase)- increases

interactions.interactions.

Solubility Rules:Solubility Rules:

Like dissolves like. Polar dissolves Like dissolves like. Polar dissolves Polar.Polar.

Practice Ex: 13.1.Practice Ex: 13.1. Ionic/polar solutes- dissolve in polar Ionic/polar solutes- dissolve in polar

solvents.solvents. Nonpolar solutes-polar solvents.Nonpolar solutes-polar solvents. Water-saltWater-salt

Solution concentrationSolution concentration

A conc is the amount of solute A conc is the amount of solute present in a specified amount of present in a specified amount of solvent or a specified amount of solvent or a specified amount of solution.solution.

Amount of solute/amount of solvent Amount of solute/amount of solvent OR amount of solute/amount of OR amount of solute/amount of solution.solution.

Percentage of Percentage of solute/ppm/ppb:solute/ppm/ppb:

% by mass= mass of solute/mass of % by mass= mass of solute/mass of soln x 100.soln x 100.

% by mass= mass of solute/ mass of % by mass= mass of solute/ mass of solute + mass of solvent x 100.solute + mass of solvent x 100.

% by volume= volume of solute/ % by volume= volume of solute/ volume of solution x 100.volume of solution x 100.

Mass-volume %= mass of solute (g)/ Mass-volume %= mass of solute (g)/ volume of solution (mL) x 100.volume of solution (mL) x 100.

Percentage of Percentage of solute/ppm/ppbsolute/ppm/ppb

Ppm(m/m) = mass of solute/mass of Ppm(m/m) = mass of solute/mass of soln x 10soln x 1066

Ppm (v/v)= volume of solute/ volume Ppm (v/v)= volume of solute/ volume of solution x 10of solution x 1066

Ppm (m/V)= mass of solute (g)/ Ppm (m/V)= mass of solute (g)/ volume of solution (mL) x 10volume of solution (mL) x 1066

In ppb use 10 In ppb use 10 99 in the above formulas. in the above formulas.

ProblemsProblems

1) What is the % by mass concentration of 1) What is the % by mass concentration of sucrose in a solution made by dissolving 5.4 g sucrose in a solution made by dissolving 5.4 g sucrose in 75.0 g water?sucrose in 75.0 g water?

2) How many grams of iodine must be added 2) How many grams of iodine must be added to 25.0 g of ethyl alcohol to prepare 5.00 % to 25.0 g of ethyl alcohol to prepare 5.00 % ethyl alcohol solution of iodine?ethyl alcohol solution of iodine?

3) A solution is made by mixing 37.8 mL of 3) A solution is made by mixing 37.8 mL of methyl alcohol with 56.2 mL water to produce methyl alcohol with 56.2 mL water to produce 80.0 mL of solution. What is the concentration 80.0 mL of solution. What is the concentration of methyl alcohol in the solution expressed as of methyl alcohol in the solution expressed as % by volume methyl alcohol?% by volume methyl alcohol?

ProblemsProblems

4) Vinegar is 5.0 % (m/v) aqueous 4) Vinegar is 5.0 % (m/v) aqueous solution of acetic acid. How much solution of acetic acid. How much acetic acid in grams is present in one acetic acid in grams is present in one teaspoon , 5.0 mL of vinegar?teaspoon , 5.0 mL of vinegar?

5) The concentration of NaF is 32.3 5) The concentration of NaF is 32.3 mg of NaF per 20.0 kg of tap water. mg of NaF per 20.0 kg of tap water. Express this concentration in ppm Express this concentration in ppm and ppb.and ppb.

Molarity:Molarity:

Molarity= M= moles of solute/liters of solution.Molarity= M= moles of solute/liters of solution. 6) Calculate the molarity of 57.2 g of NH4Br 6) Calculate the molarity of 57.2 g of NH4Br

dissolved in enough water to give 2.15 L of dissolved in enough water to give 2.15 L of solution.solution.

7) How many grams of H3C6H5O7 are present 7) How many grams of H3C6H5O7 are present in 125 mL of 0.400 M citric acid solution?in 125 mL of 0.400 M citric acid solution?

8) How many liters of 0.100 M aqueous solution 8) How many liters of 0.100 M aqueous solution of NaOH can be prepared from 10.0 g of NaOH?of NaOH can be prepared from 10.0 g of NaOH?

problemsproblems

9) A 40.00 % by mass aqueous solution of 9) A 40.00 % by mass aqueous solution of formic acid ( HCHO2) has a density of 1.098 formic acid ( HCHO2) has a density of 1.098 g/mL What is the molarity of the solution?g/mL What is the molarity of the solution?

10) A 2.342 M H2SO4 solution has a density 10) A 2.342 M H2SO4 solution has a density of 1.142 g/mL How many grams of solvent are of 1.142 g/mL How many grams of solvent are present in 25.0 mL of this solution?present in 25.0 mL of this solution?

11) A 0.900 M acetic acid solution has a 11) A 0.900 M acetic acid solution has a density of 1.10 g/mL How many grams of density of 1.10 g/mL How many grams of solvent are present in 125 mL of this solvent are present in 125 mL of this solution?solution?

MolalityMolality

m= moles of solute/kilograms of m= moles of solute/kilograms of solvent solvent

DilutionDilution

Process in which more solvent is Process in which more solvent is added to a specific volume of added to a specific volume of solution to lower its concentration.solution to lower its concentration.

M1 x V1 =M2 x V2.M1 x V1 =M2 x V2.

ProblemsProblems

12) What is the molarity of the solution 12) What is the molarity of the solution prepared by diluting 65mL of 0.95 M nitric prepared by diluting 65mL of 0.95 M nitric acid solution to a final volume of 135 mL acid solution to a final volume of 135 mL through addition of solvent?through addition of solvent?

13) How much solvent in milliliters must be 13) How much solvent in milliliters must be added to 200.0 mL of 1.25 M NaCl solution to added to 200.0 mL of 1.25 M NaCl solution to decrease its concentration to 0.770 M? decrease its concentration to 0.770 M?

14) What is the molarity of the solution 14) What is the molarity of the solution obtained by mixing 50.0 mL of 2.25 M HCl obtained by mixing 50.0 mL of 2.25 M HCl solution with 160.0mL of 1.25 M HCl solution?solution with 160.0mL of 1.25 M HCl solution?

ProblemsProblems

15) What volume of 0.30 M Cu(OH) 2 15) What volume of 0.30 M Cu(OH) 2 solution is needed to react with 500 solution is needed to react with 500 mL of 0.100 M H3PO4 solution? mL of 0.100 M H3PO4 solution?

3 Cu(OH)2(aq) + 2H3PO4(aq) → 3 Cu(OH)2(aq) + 2H3PO4(aq) →

Cu3(PO 4 )2 + 6 H2O(l) Cu3(PO 4 )2 + 6 H2O(l)

ProblemsProblems

16) How many grams of KCl (molar 16) How many grams of KCl (molar mass = 74.55 g) will be produced mass = 74.55 g) will be produced from the reaction of 50.0 mL of 0.300 from the reaction of 50.0 mL of 0.300 M KOH with excess HCl? M KOH with excess HCl?

KOH (aq) + HCl(aq) → KCl(aq) + KOH (aq) + HCl(aq) → KCl(aq) + HCl(aq)HCl(aq)

ProblemsProblems

17) What volume, in liters, of 0.150 17) What volume, in liters, of 0.150

Ba(OH)Ba(OH)22 solution is needed to react solution is needed to react completely with 0.200 L of a 0.300 M completely with 0.200 L of a 0.300 M HNO3 solution according to the HNO3 solution according to the equation equation

Ba(OH)2 + 2HNO3 → Ba(NO3)2 + Ba(OH)2 + 2HNO3 → Ba(NO3)2 + 2H2O 2H2O