Version 001 – Exam 3 – David Laude (53015) 1This print-out should have 30 questions.Multiple-choice questions may continue onthe next column or page – find all choicesbefore answering. V1:1, V2:1, V3:1, V4:1,V5:2.Please make sure you write your versionnumbers on your scantron. Good luck!Half Rctn Potential26:09, general, multiple choice, > 1 min, fixed.001 (part 1 of 1) 6 pointsThe equilibrium constant for the following cellK | K+|| Ce4+| Ce3+| Ptis K = 5.518×1076. What is E◦redof the K+/Khalf-reaction? Assume the reaction is takingplace at room temperature (T = 25◦C).Ce4++ e−→ Ce3+E◦red= +1.61 V1. −2.93 V correct2. +4.54 V3. −8.84 V4. +2.93 V5. −4.54 VExplanation:Cell Stoic26:04, general, multiple choice, > 1 min, fixed.002 (part 1 of 1) 6 pointsThe reaction2 Ag+(aq) + Fe(s) → Fe2+(aq) + 2 Ag(s)taking place in a battery generates a currentof 2 Amp. How much Fe(s) is consumed in 1hour?1. 2.08 g correct2. 4.16 g3. 8.32 g4. 3.46 × 10−2g5. 1.04 gExplanation:Cell Potential26:08, general, multiple choice, < 1 min, fixed.003 (part 1 of 1) 6 pointsWhat is the cell potential of the following cell?Pt | Br−(aq, 0.2 M) | Br2(`) ||Au+(aq, 0.7 M) | AuBr2+ 2 e−→ 2 Br−E◦red= +1.09 VAu++ e−→ Au E◦red= +1.69 V1. 0.55 V correct2. 0.60 V3. 0.65 V4. 0.48 V5. 0.72 VExplanation:Battery Use27:03, general, multiple choice, < 1 min, fixed.004 (part 1 of 1) 6 pointsWhich of the following is not a correct state-ment about a popular battery used in ourdaily lives?1. Calcium oxide is the base most commonlyfound in alkaline batteries. correct2. “Hybrid” automobiles most often employa nickel metal hydride battery as their electri-cal power source.3. Sulfuric acid is the acid most commonlyfound in lead acid storage batteries.4. Nickel cadmium batteries are decreasinglypopular because memory effects reduce thelifetime of the battery.5. Lithium ion batteries, which are used incell phones, are considered by some to be asafety risk because of explosion or fire.Explanation:Version 001 – Exam 3 – David Laude (53015) 2Rctn Rate 0220:01, general, multiple choice, < 1 min, fixed.005 (part 1 of 1) 6 pointsIn the reaction3 Mg(s) + 2 Fe2+(aq) →2 Fe(s) + 3 Mg2+(aq) ,∆[Fe]∆t= 2.4 × 10−4M/s. What is∆[Mg]∆t?1. −3.6 × 10−4M/s correct2. +3.6 × 10−4M/s3. −1.6 × 10−4M/s4. +1.6 × 10−4M/s5. +1.2 × 10−4M/sExplanation:Rctn Order 0120:03, general, multiple choice, < 1 min, fixed.006 (part 1 of 1) 6 pointsA reaction has a rate constant of k = 5.5 ×10−4M2s−1. What is the reaction order?1. −1 correct2. −23. 04. 15. 2Explanation:Rate Law 0320:03, general, multiple choice, < 1 min, fixed.007 (part 1 of 1) 6 pointsIf k = 2.7 × 10−6M−1s−1for the reactionA → Bwhich of the following is the correct rate law?1. rate = k [A]2correct2. rate = k [A]13. rate = k [A]04. rate = k [A]2[B]−15. rate = k [A]0[B]−1Explanation:Rate Law 0420:02, general, multiple choice, > 1 min, fixed.008 (part 1 of 1) 6 pointsWhat is the rate law for the reactionA + B + C → Dif the following data were collected?Exp [A]0[B]0[C]0Initial Rate1 0.4 1.2 0.7 2.32 × 10−32 1.3 1.2 0.9 7.54 × 10−33 0.4 4.1 0.8 9.25 × 10−24 1.3 1.2 0.2 7.54 × 10−31. rate = 3.36 × 10−3[A]1[B]3[C]0correct2. rate = 5.37 × 10−3[A]1[B]3[C]03. rate = 1.49 × 10−3[A]0[B]3[C]14. rate = 1.79 × 10−3[A]0[B]2[C]15. rate = 4.48 × 10−3[A]1[B]2[C]1Explanation:Decomp Time20:04, general, multiple choice, > 1 min, fixed.009 (part 1 of 1) 6 pointsThe decomposition of hydrogen peroxide toform water is a first order process. If it takes20 minutes for the initial concentration to fallfrom 1.6 M to 0.8 M, how much time haspassed when only 0.05 M remains?1. 100 minutes correct2. 40 minutesVersion 001 – Exam 3 – David Laude (53015) 33. 120 minutes4. 160 minutes5. 80 minutesExplanation:Zero Order Rate20:04, general, multiple choice, > 1 min, fixed.010 (part 1 of 1) 6 pointsFor the reaction2 A → Bthe concentration of [A] after 15 hours is 0.15M. How much of compound [A] was initiallypresent if k = 2.16 × 10−7M/s?1. 1.733 × 10−1M correct2. 1.504 × 10−1M3. 1.535 × 10−1M4. 1.617 × 10−1M5. 7.32 × 10−2MExplanation:Rate Plot20:04, general, multiple choice, < 1 min, fixed.011 (part 1 of 1) 6 pointsThe graph is a plot of ln A vs t for the reactionA → B1 2 3 4 50.20.40.60.81.01.2rate = k [A] is the rate law for this reaction.What was the initial concentration of [A]?1. 3.0 M correct2. 1.8 M3. 1.1 M4. 5 M5. 0.6 MExplanation:Sparks collision 00120:08, general, multiple choice, < 1 min, fixed.012 (part 1 of 1) 6 pointsWhich of the following statements regardingcollision and transition state theory are true?I) Reactants must collide to form products.II) Activation energy is always positive.III) Reactant molecules must absorb energyto form the transition state.IV) Reactant collisions must be orientedproperly to form products.1. I, III, and IV only2. I, II, III, and IV correct3. I and IV only4. II and III only5. II, III, and IV onlyExplanation:Rctn Rate 0320:09, general, multiple choice, < 1 min, fixed.013 (part 1 of 1) 6 pointsWhich of the following can increase the rateof reaction by increasing the rate constant k?I. raising the temperatureII. decreasing the volumeIII. adding a catalystIV. increasing the concentration1. I and III only correct2. I, II, and III onlyVersion 001 – Exam 3 – David Laude (53015) 43. I only4. II only5. III and IV onlyExplanation:Activ Energy 0120:07, general, multiple choice, > 1 min, fixed.014 (part 1 of 1) 6 pointsThe reaction2 HI → H2+ I2has rate constants k1= 9.7×10−6M−1s−1andk2= 9.7×10−2M−1s−1at T1= 326.85◦C andT2= 526.85◦C. What is the activation energyof this reaction?1. 1.84 × 105J correct2. 2.86 × 104J3. 7.16 × 107J4. 7.93 × 103J5. 6.59 × 104JExplanation:Rate Law 0820:06, general, multiple choice, > 1 min, fixed.015 (part 1 of 1) 6 pointsWhat would you propose as the rate law forthe reaction of bromine with nitric oxide if thesecond step of a proposed mechanism is therate determining step?Step 1: NO + Br2→ NOBr2Step 2: NOBr2+ NO → 2 NOBr1. k [NO]2[Br2] correct2. k [NO] [Br2] [NOBr2]3. k [NO]24. k [NO] [Br2] [NOBr2]−15. k [NO]2[Br2] [NOBr2]−1Explanation:Activ Energy20:09, general, multiple choice, < 1 min, fixed.016 (part 1 of 1) 6 pointsThe graph describes the energy profile of areaction.ABTimeEnergy (kJ)50300400What are the values for ∆H and Ea, respec-tively, for the reaction in the direction writ-ten?1.
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