SolutionsSolutions

Ch.12 & 13Ch.12 & 13

LiquidsLiquids

Condensed StatesCondensed States Liquids and SolidsLiquids and Solids

Higher densitiesHigher densities Slightly compressibleSlightly compressible Slow diffusion(mixing)Slow diffusion(mixing)

Physical state depends on strength of Physical state depends on strength of attraction between particlesattraction between particles

Gases: weak forces of attractionGases: weak forces of attraction Liquids: stronger forcesLiquids: stronger forces Solids: really strong forcesSolids: really strong forces Forces of attractionForces of attraction intermolecular intermolecular

forcesforces

Properties of LiquidsProperties of Liquids ViscosityViscosity

Friction, resistance to motionFriction, resistance to motion syrup vs. watersyrup vs. water

Stronger intermolecular forces =Stronger intermolecular forces = greater viscositygreater viscosity

Low temperaturesLow temperatures greater viscositygreater viscosity

Properties of LiquidsProperties of Liquids

Surface TensionSurface Tension Tight film on surface of waterTight film on surface of water Uneven forces at surfaceUneven forces at surface Causes rain to fall in drops!Causes rain to fall in drops! Video - 30Video - 30

SolutionsSolutions

Properties of SolutionsProperties of Solutions

Homogenous mixturesHomogenous mixtures

1.1. Particles are very smallParticles are very small

2.2. Particles mixed evenlyParticles mixed evenly

3.3. Particles will not separateParticles will not separate Made of Made of solutesolute (gets dissolved) and (gets dissolved) and

solventsolvent (does the dissolving) (does the dissolving)

Properties of SolutionsProperties of Solutions

Soluble Soluble - substance dissolves in - substance dissolves in another substanceanother substance

InsolubleInsoluble – substance does NOT – substance does NOT dissolvedissolve

Types of SolutionsTypes of Solutions Solid SolutionsSolid Solutions

AlloysAlloys: mixture of 2 or more metals: mixture of 2 or more metals Melting the metals, mixing and coolingMelting the metals, mixing and cooling Sterling silver: silver and copperSterling silver: silver and copper

Gaseous Solutions:Gaseous Solutions: Mixture of gases (air) Mixture of gases (air)

Types of SolutionsTypes of Solutions

Liquid Solutions:Liquid Solutions: Solvent and Solution are liquidsSolvent and Solution are liquids Solute: solid, liq. or gasSolute: solid, liq. or gas

Mixing liquids:Mixing liquids: MiscibleMiscible: liquids that mix thoroughly: liquids that mix thoroughly ImmiscibleImmiscible: liquids that cannot mix: liquids that cannot mix

Types of SolutionsTypes of Solutions

Aqueous Solutions:Aqueous Solutions: Water is “universal solvent”Water is “universal solvent”

Ionic compounds dissolve to give ionsIonic compounds dissolve to give ions Solution conducts electricity - Solution conducts electricity - electrolyteelectrolyte Solutions that do not - Solutions that do not - nonelectrolytenonelectrolyte

SolubilitySolubility

Ch.12 Section 2Ch.12 Section 2

SolubilitySolubility Def:Def: amount of solute that will dissolve amount of solute that will dissolve

in a specific solventin a specific solvent Temp.Temp. and and Pressure(gas)Pressure(gas) given with given with

solubilitysolubility Solubility can be altered by:Solubility can be altered by:

Type of Solvent (Polar/Nonpolar)Type of Solvent (Polar/Nonpolar) Surface area of solute particlesSurface area of solute particles Molar Mass of solute or solventMolar Mass of solute or solvent PressurePressure Temperature of solventTemperature of solvent

Type of SolventType of Solvent

““Like dissolves like”Like dissolves like” Water is polar Water is polar will only dissolve polar will only dissolve polar

solutessolutes Paint thinner and gasoline are nonpolarPaint thinner and gasoline are nonpolar SOAP – universal polar and nonpolar endsSOAP – universal polar and nonpolar ends

Surface AreaSurface Area

Solvents can only dissolve the surface of Solvents can only dissolve the surface of the solute particlesthe solute particles

Smaller particles dissolve fasterSmaller particles dissolve faster Stirring also increases # of collisionsStirring also increases # of collisions

Mass of Solute or SolventMass of Solute or Solvent

A large molar mass SOLUTE will need A large molar mass SOLUTE will need more energy to break up particlesmore energy to break up particles

A large molar mass SOLVENT has more A large molar mass SOLVENT has more energy to break up soluteenergy to break up solute

PressurePressure

Mainly affects solubility of gas solutesMainly affects solubility of gas solutes Henry’s LawHenry’s Law: solubility of gas is directly : solubility of gas is directly

proportional to partial pressure of the gas proportional to partial pressure of the gas on the liquid.on the liquid.

Video - 48Video - 48

TemperatureTemperature

Higher temp. = faster particles = harder Higher temp. = faster particles = harder collisions = smaller particlescollisions = smaller particles

Allows solute to mix in with solvent fasterAllows solute to mix in with solvent faster

Heats of SolutionHeats of Solution

Energy is involved in forming solutionsEnergy is involved in forming solutions EndothermicEndothermic rxnrxn: a rxn that absorbs heat : a rxn that absorbs heat

(feels cold)(feels cold) Exothermic rxnExothermic rxn: a rxn that gives off heat : a rxn that gives off heat

(feels warm)(feels warm)

SaturationSaturation

Limit to amount of solute that can be Limit to amount of solute that can be dissolved in solventdissolved in solvent

A solution is A solution is saturatedsaturated when no more when no more solute can be dissolved - reached solute can be dissolved - reached equilibriumequilibrium Add more solute and doesn’t dissolveAdd more solute and doesn’t dissolve

SaturationSaturation

Unsaturated Unsaturated solution has solution has lessless than the than the max amount of solute that can be max amount of solute that can be dissolveddissolved

SupersaturatedSupersaturated solution has a greater solution has a greater amount of solute than needed to get a amount of solute than needed to get a saturated solutionsaturated solution

ConcentrationConcentration

Ch.12 Section 3Ch.12 Section 3

Concentration of SolutionsConcentration of Solutions

ConcentrationConcentration: amount of solute in a : amount of solute in a given amount of solvent or solutiongiven amount of solvent or solution

Concentrated: a lot of solute in solventConcentrated: a lot of solute in solvent Dilute: small amt of solute in solventDilute: small amt of solute in solvent

Concentration of SolutionsConcentration of Solutions

Most common unit is Most common unit is Molarity (M)Molarity (M) MM = = moles of solutemoles of solute

liters of solutionliters of solution

Molarity ExamplesMolarity Examples What is the molarity of a .100 L solution of What is the molarity of a .100 L solution of

NaOH if 10.0 g of NaOH were dissolved?NaOH if 10.0 g of NaOH were dissolved? How many grams of CaClHow many grams of CaCl22 are needed to are needed to

make a 1.00 make a 1.00 MM solution? solution? What volume is required to make a 3.0 What volume is required to make a 3.0 MM

with 5.50 mol NaCl?with 5.50 mol NaCl?

Making SolutionsMaking Solutions

How would you make 250 mL of 6.00 How would you make 250 mL of 6.00 MM NaOH solution? NaOH solution?

Concentration of SolutionsConcentration of Solutions MolalityMolality ( (mm)) mm = = moles of solutemoles of solute

kilograms of solventkilograms of solvent What is the molality of a solution if 18.0 What is the molality of a solution if 18.0

g Cg C66HH1212OO66 (180. g/mol) is dissolved in (180. g/mol) is dissolved in

3.0 x 103.0 x 1033 g of water? g of water?

Solution Solution StoichiometryStoichiometryLimiting Reactant is Back!Limiting Reactant is Back!

Solution StoichiometrySolution Stoichiometry

Mix 2 aqueous sol’ns a rxn Mix 2 aqueous sol’ns a rxn couldcould occur occur If rxn occurs, get precipitateIf rxn occurs, get precipitate

Limiting Reactant controls amt of productLimiting Reactant controls amt of product BUT NOW…BUT NOW… Our reactants are not solids, we have Our reactants are not solids, we have

AQUEOUS SOLUTIONSAQUEOUS SOLUTIONS How do we get moles of our reactants?How do we get moles of our reactants?

Getting Moles of ReactantsGetting Moles of Reactants

Aqueous solutions are given in Aqueous solutions are given in MOLARITYMOLARITY..

Ex: 6 Ex: 6 MM = = 6 moles of solute6 moles of solute

1 L of sol’n1 L of sol’n Get Moles from Molarity!!Get Moles from Molarity!!

ExampleExample Zn(NOZn(NO33))22((aqaq) + Na) + Na22COCO33((aqaq) ) ZnCO ZnCO33((ss) + NaNO) + NaNO33((aqaq))

What mass of ppt can be formed when What mass of ppt can be formed when 50.0 mL of 2.0 50.0 mL of 2.0 MM Zn(NO Zn(NO33))22 reacts with reacts with

35.0 mL of 2.0 35.0 mL of 2.0 MM Na Na22COCO33??

• Write balanced equation:Write balanced equation:• Find moles of each reactant:Find moles of each reactant:• Convert moles of reactant Convert moles of reactant moles of ppt moles of ppt

mass of ppt mass of ppt

ExamplesExamples 0.55 g of ppt, Cu(OH)0.55 g of ppt, Cu(OH)22 is formed when is formed when

excess CuSOexcess CuSO44 solution is mixed with solution is mixed with

75.0 mL of NaOH solution. What is 75.0 mL of NaOH solution. What is the concentration of NaOH?the concentration of NaOH?

• Write balanced equation:Write balanced equation:• Find moles of NaOH:Find moles of NaOH:• Calculate Molarity:Calculate Molarity:

ExamplesExamples

What volume of 0.500 M HBr is required What volume of 0.500 M HBr is required to react with 250 mL of 1.00 M NaOH?to react with 250 mL of 1.00 M NaOH?

Balanced EquationBalanced Equation Find Moles NaOH Find Moles NaOH moles HBr moles HBr Use moles HBr Use moles HBr L of HBr L of HBr

Changing Changing ConcentrationConcentration

Changing ConcentrationChanging Concentration

1.1. Add more solventAdd more solvent• Diluting the solutionDiluting the solution• Less concentrated solutionLess concentrated solution

2.2. Decrease solvent/ Add soluteDecrease solvent/ Add solute• Evaporation of solventEvaporation of solvent• Adding more soluteAdding more solute• More concentrated solutionMore concentrated solution

DILUTIONDILUTION Only use dilution when need concentration Only use dilution when need concentration

LESS THAN what you start withLESS THAN what you start with MMooVVoo = M = MnnVVnn

M = molarity of M = molarity of total solutiontotal solution V = volume of V = volume of total solutiontotal solution Concentration has to be in molarityConcentration has to be in molarity Volume units just have to be the same!Volume units just have to be the same!

MMooVVoo = M = MnnVVnn

You have 25.0 mL of a 10.0 You have 25.0 mL of a 10.0 MM solution solution of NaCl. You only need it to be 2.50 of NaCl. You only need it to be 2.50 MM. . What must your volume be to make this What must your volume be to make this solution?solution?

How much water do you need to add?How much water do you need to add?

Ionic Reactions in Ionic Reactions in SolutionsSolutions

Ch. 13Ch. 13

Ionic SolutionsIonic Solutions When water dissolves the solute, the When water dissolves the solute, the

ions of solute are ions of solute are hydratedhydrated Ionic crystals that “trap” water with in Ionic crystals that “trap” water with in

themselves are themselves are hydrateshydrates Ex: CuSOEx: CuSO44• 5H• 5H22OO Copper(II) sulfate pentahydrateCopper(II) sulfate pentahydrate

Ionic SolutionsIonic Solutions DissociationDissociation = when ions separate= when ions separate NaCl(s) NaCl(s) NaNa+1+1(aq) + Cl(aq) + Cl--(aq)(aq) If 1 mole of NaCl dissolves then 1 mole If 1 mole of NaCl dissolves then 1 mole

of each ion producedof each ion produced Remember Molar Ratios!!!Remember Molar Ratios!!! CaClCaCl22(s) (s) CaCa+2+2(aq) + 2Cl(aq) + 2Cl--(aq)(aq) 1 mol1 mol 1 mol1 mol 2 mol 2 mol

H2O

H2O

Ionic SolutionsIonic Solutions Not all ionic compounds are soluble in Not all ionic compounds are soluble in

waterwater Table of Solubility Rules!Table of Solubility Rules! Can determine whether a compound will Can determine whether a compound will

dissolvedissolve Soluble or Insoluble in water?Soluble or Insoluble in water?

Copper(II) carbonateCopper(II) carbonate Sodium hydroxideSodium hydroxide Silver chlorideSilver chloride Potassium sulfatePotassium sulfate

Double-Replacement RxnsDouble-Replacement Rxns

AX + BY AX + BY AY + BX AY + BX Mix two aqueous ionic solutions Mix two aqueous ionic solutions NaINaI(aq)(aq) + Pb(NO + Pb(NO33))2(aq)2(aq) Products and their phases?Products and their phases? The solid formed during a reaction is the The solid formed during a reaction is the

precipitateprecipitate

Net Ionic EquationsNet Ionic Equations Def: Def: An equation that shows only those An equation that shows only those

compounds and ions that undergo a compounds and ions that undergo a chemical change.chemical change.

Ions that do not take part in the Ions that do not take part in the chemical reaction and are found in the chemical reaction and are found in the solution before and after the reaction solution before and after the reaction are are spectator ionsspectator ions..

Net Ionic EquationsNet Ionic Equations

Rubidium phosphate + Titanium(IV) nitrateRubidium phosphate + Titanium(IV) nitrate

Ammonium sulfate + magnesium chlorideAmmonium sulfate + magnesium chloride

Calcium hydroxide + Cobalt(II) acetateCalcium hydroxide + Cobalt(II) acetate

Write the Complete ionic equation, the Write the Complete ionic equation, the Net Ionic Equation and list the spectator Net Ionic Equation and list the spectator ions for the following aqueous solutions:ions for the following aqueous solutions:

Rubidium hydroxide + hydrochloric acidRubidium hydroxide + hydrochloric acid Ammonium nitrate + Cesium phosphateAmmonium nitrate + Cesium phosphate Boron sulfate + Potassium hydroxideBoron sulfate + Potassium hydroxide Strontium chloride + Lead(II) nitrateStrontium chloride + Lead(II) nitrate