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signature:139version numberYasmeen Zubair(ykz57)EXAM 1Sparks Class (50155)Water DataKf= 1.86◦C/mKb= 0.512◦C/mCice= 2.09 J/g◦CCwater= 4.184 J/g◦CCsteam= 2.09 J/g◦CΔHfusion= 334 J/gΔHvapor= 2260 J/gPlease refer to the back of the bubble sheet for more info.NOTE:Please keep your Exam copy intact (all pages still stapled). You must turn in yourexam copy, plus your bubble sheet, scratch paper, and your free response section.
Version 139 – Exam 1 – sparks – (50155)2Thisprint-outshouldhave20questions.Multiple-choice questions may continue onthe next column or page – find all choicesbefore answering.0014.0pointsThe lattice energy of NaBr is 735 kJ/mol. Theheat of hydration for NaBr is -736 kJ/mol.What is the ΔHsolnfor NaBr dissolving inwater?1.negative ; small1.1471 kJ/mol2.none of the other answers is correct3.+1 kJ/mol4.-1471 kJ/mol5.-1 kJ/molcorrectExplanation:None0024.0pointsIdentify the FALSE statement aboutKsp.1.Kspis dependent on temperature.2.Kspis called the solubility product for asaturated solution.3.Kspis used to describe salt solutionswhere the minimum amount of salt has beendissolved into the solvent.correct4.Kspis a constant that is specific to eachcompound.5.Kspis a function of the concentrations ofions coming from a given salt.Explanation:Kspis used to describe a solution at satura-tion which is a condition with themaximumconcentration of ions is present (not mini-mum).0034.0pointsA compound is extremely soluble in water.2.negative ; largecorrect3.positive ; small4.positive ; largeExplanation:extremely soluble = spontaneous = nega-tive ΔGextremely soluble = much higher concen-trations when saturated which means a largevalue forKsp0044.0pointsWhat isKspfor Ag3PO4, if its molar solubilityis 2.7×10−6mol/L?1.5.3×10−232.1.7×10−143.5.3×10−164.2.0×10−175.4.8×10−226.7.3×10−127.1.4×10−21correctExplanation:S= 2.7×10−6mol/LThe solubility equilibrium isAg3PO4(s)⇀↽3 Ag+(aq) + PO3−4(aq)[Ag+] = 3S= 8.1×10−6mol/L[PO3−4] =S= 2.7×10−6mol/LKsp= [Ag+]3[POYou would expect ΔGfor this dissolutionprocess to be (negative/positive) and that thiscompound would have a (large/small)Kspvalue.