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Version 025 – Make up Exam 1 – laude – (51155)1Thisprint-outshouldhave30questions.Multiple-choice questions may continue onthe next column or page – find all choicesbefore answering.0016.0pointsRank the following salts from greatest to leastmolar solubility:A container holds a mixture of acetone andwater at 40◦C. Ifχacet, the mole fractionof acetone, is 0.1, what is the total vaporpressure?(The equilibrium vapor pressuresfor pure acetone and pure water at 40◦C areroughly 400 torr and 50 torr respectively.)A) AgIKsp= 8.52×10−17B) ZnFKsp= 0.0304C) PbSO4Ksp= 2.53×10−8D) CsClO4Ksp= 0.003951.B>D>A>C2.B>D>C>Acorrect3.D>C>B>A4.D>B>C>AExplanation:All of the salts are composed of a singlecation and anion, so the solubility of each isthe square root of its Ksp.0026.0pointsConsider the reaction,A(aq) + B(aq)←→C(aq)The equilibrium constant,K, is 10.If youdissolved 0.2 moles of A, 1.0 moles of B and1.6 moles of C in 2 liters of water, which ofthe following would occur.1.the reaction would move right2.the reaction would move leftcorrect3.nothing would occur4.not enough information0036.0points1.50 torr2.40 torr3.365 torr4.85 torrcorrect5.400 torrExplanation:P=PH2O+Pacet=χH2OP◦H2O+χacetP◦acet= (1-χacet)P◦H2O+χacetP◦acet= (0.9)(50) + (0.1)(400)= 850046.0pointsRank the following liquids by their misci-bility in heptane (C7H16), from most miscibleto least: NH3, CH3OH, CH3CH2F, CCl4.1.CCl4>CH3CH2F>NH3>CH3OH2.CH3CH2F>CCl4>CH3OH>NH33.CCl4>CH3CH2F>CH3OH>NH3correct4.NH3>CH3OH>CH3CH2F>CCl45.CH3CH2F>CH3OH>CCl4>NH3
Version 025 – Make up Exam 1 – laude – (51155)2and very polar (exhibiting hydrogen bond-ing), and ammonia is the most polar of theliquids, and thus least soluble.0056.0pointsIf 100 mL of 0.2 M CHOOH and 400 mLof 0.5 M NaCHOO are mixed, what is the pHof the resulting solution? Assume the pKaofformic acid is 3.7.