Chem 1ALecture 9HomeworkRead chapter 4 ALEKS homework: XM4NG-QNDN6Chapter 4 book problemsRecap• Theoretical Yield • Actual Yield• Percent Yield• Solution – solvent, solute, aqueous solution, soluble and insoluble• Water - Dissociations of Ionic Compounds • Electrolytes and non-electrolytes • Molarity • Dilution : M1V1= M2V2• Not all ionic compounds dissolve in water. • AgCl does not dissolve in water. • AgCl remains as a solid, AgCl(s), within the liquid water.• It does not dissolve into independent ions.Ionic Compounds in WaterTypes of Chemical Reactions and Solution Stoichiometry Reactions in aqueous solution. Aqueous => waterSolubilitySolubilitySolubilityKCl(aq) + AgNO3(aq)Observe white precipitateWhat is the precipitate?PrecipitationFrom the Greek, “To Transpose”AX + BY  AY + BXAgNO3(aq) + KCl(aq)  AgCl(s) + KNO3(aq)For a metathesis reaction to occur, ions must be removed from the solution.1. The formation of an insoluble solid (a precipitate).2. The formation of either a soluble weak electrolyte or soluble nonelectrolyte.3. The formation of a gas. Metathesis Reactions• The cation from one compound can now pair with the anion from the other compound to form new (and potentially insoluble) products. If the potentially insoluble products are both soluble,then no reaction occurs.If one or both of the potentially insoluble products are insoluble, a precipitation reaction occurs. Precipitation Reactions1. Write and equation with the reactants and then combine the cation from one reactant with the anion from the other. **Make sure to write correct (charge-neutral) formulas for the new ionic compounds.**2. Use the solubility rules to determine whether any of the potential new products are indeed insoluble.3. If all of the potentially insoluble products are soluble, there will be no precipitate. Write NO REACTION next to the arrow.4. One of the potentially insoluble products is insoluble, so write its formula as the product of the reaction, using (s) to indicate solid. Write the soluble product with (aq) to indicate aqueous.5. Balance the equationPrecipitation ReactionsMolecular Equation:Mg(NO3)2(aq) + 2NaOH(aq)  Mg(OH)2(s) + 2NaNO3(aq) Complete Ionic Equation:Mg2+(aq) + 2NO3-(aq) + 2Na +(aq) + 2OH-(aq)  Mg(OH)2(s) + 2Na +(aq) + 2NO3-(aq)Spectator Ions – Are ions that appear in identical forms among both the reactants and the products. EquationsWhen spectator ions are omitted from the complete ionic equation, we are left with the net ionic equation.Complete Ionic Equation:Mg2+(aq) + 2NO3-(aq) + 2Na +(aq) + 2OH-(aq)  Mg(OH)2(s) + 2Na +(aq) + 2NO3-(aq)Net Ionic Equation:Mg2+(aq) + 2OH-(aq)  Mg(OH)2(s) Net Ionic EquationWrite the net ionic equations for the reactions that occur when solutions of the following compounds are mixed.a) KOH and Co(NO3)2 b) NaCl and (NH4)2SO4PracticeA. KNO3(s)B. N3–(aq)C. PbI2(aq)D. PbI(s) E. None of the aboveWhich of the following is a term in the complete ionic equation for the following reaction?KI(aq) + Pb(NO3)2(aq) →A. KNO3(s)B. N3–(aq)C. PbI2(aq)D. PbI(s) E. None of the aboveWhich of the following is a term in the complete ionic equation for the following reaction?KI(aq) + Pb(NO3)2(aq) →A. Li+and H+B. Li+and NO3–C. Li+and OH–D. H+and OH–E. All of the aboveWhat are the spectator ions for the following reaction?LiOH(aq) + HNO3(aq) →A. Li+and H+B. Li+and NO3–C. Li+and OH–D. H+and OH–E. All of the aboveWhat are the spectator ions for the following reaction?LiOH(aq) + HNO3(aq) →a) 0.6 molb) 0.2 molc) 0.4 mold) 0.13 mole) 0.07 molWhen 100.0 mL of 2.0 M Al(NO3)3is added to 200.0 mL of 2.0 M KOH, how many moles of Al(OH)3can be produced ?Arrhenius’s definition: when dissolved in water increases H+concentration of water.BrØnsted’s definition: proton donorExamples: HCl, HNO3, H2SO4, CH3CO2HHCl (aq) + H2O(l)  H3O+(aq) + CI-(aq) HCl (aq)  H+(aq) + CI-(aq)Monoprotic – yield one H atom per molecule of acid.Diprotic - yield two H atoms per molecule of acid. H2SO4(aq)  H+(aq) + HSO4-(aq)HSO4-(aq) ⇋ H+(aq) + SO42-(aq)AcidsArrhenius’s definition: when dissolved in water increases OH-concentration of water.BrØnsted’s definition: proton acceptorExamples: NaOH, KOH, NH3NaOH (aq)  Na+(aq) + OH-(aq) NH3(aq) + H2O(l)  NH4+(aq) + OH-(aq)Amphiprotic – can react as either an acid or a base.BasesHCl is an acidAn acid increases [H+] in solutionNaOH is a baseA base increases [OH–] in solution[H+] > [OH–] acidic solution[H+] = [OH–] neutral solution[H+] < [OH–] basic solutionAcid Base Reactions• Neutralization reactions between an acid and a metal hydroxide produces water and a salt (an ionic compound). Acid–base reactions.Net Ionic Equation for strong acid + strong base?Neutralization ReactionsSolution 1: 1.0 M NaOHSolution 2: 1.0 M Ca(OH)2Which solution would require more HCl to be neutralized?a) NaOH b) Ca(OH)2c) More information is needed to answer this questionSolution 1: 1.0 M NaOHSolution 2: 1.0 M Ca(OH)2Which solution would require more HCl to be neutralized?a) NaOH b) Ca(OH)2c) More information is needed to answer this question1.0 M NaOH100 mL HCl[HCl] = ?Titrate 100 mL HCl solution with 1.0 M NaOHphenophthalein (indicator)TitrationTitrationUsed to determine the concentration of a solution:Analyte: the solution of unknown concentration (but known volume)Titrant: the solution of known concentration.Equivalence Point: the point at which exactly the right volume of titrant has been added to complete the reactionReading a Burette3.90 mL – 3.30 mL = 0.6 mL(Richard Megna /Fundamental Photographs)TitrationBurette: 1.0 M NaOHInitial Volume: 5.0 mLFinal Volume (at end point): 33.5 mLFor the 100 mL HCl solution, calculate [H+].a) 1.0 M b) 0.285 M c) 0.335 M d) 0.05 M e) not sureTitrationBurette: 1.0 M NaOHInitial Volume: 5.0 mLFinal Volume (at end point): 33.5 mLReaction as you titrate: H++ OH- H2OAt the End Point: color change observed  moles H+ = moles OH–For the 100 mL HCl solution, calculate [H+].a) 1.0 M b) 0.285 M c) 0.335 M d) 0.05 M e) not sureTitration2HCl(aq) + Na2S(aq)  H2S(g) + 2NaCl(aq)Net Ionic Equation:Gas Forming ReactionsMg(s) + 2HCl (aq)  MgCl2(aq) + H2(g)Mg(s) + 2H+(aq)  Mg2+(aq) + H2(g)Oxidation – when a substance loses electrons.Reduction - when a