CHM1046 Final Exam Questions And Answers Solved Graded A+

Water bugs would find it most difficult to walk on which liquid? - correct answers Cl2 If I wanted to look up the equilibrium constant (K) for the following reaction: AgCN (aq) - Ag+ (aq) + CN- (aq) Which table would you search for? - correct answers Kd table Which of the following can be used to make a buffer? - correct answers NH3/NH4+ Which describes the flow of electrons in a galvanic cell? - correct answers From the anode to the cathode through the external circuit Consider the standard electrode potentials: Hg2+ (aq) + 2e-- - Hg (s)E=0.85V Cr3+ (aq) + 3e-- - Cr (s)E= -0.74V and the following reaction: 2Cr (s) + 3Hg2+ (aq) -- 3Hg(s)+2Cr3+ (aq) What is the cell potential, in V, for this REDOX reaction? - correct answers +1.59 Which metal electrode will gain mass over the course of operating this galvanic cell? - correct answers Hg (s) Based on the change in DELTAG, the overall reaction is: - correct answers non-spontaneous The reaction intermediate is: - correct answers HRnOCl The catalyst for this reaction is: - correct answers Rn For the overall equilibrium constant for this reaction: HOCL - H+ OCl - correct answers K 1 How many elementary steps are there? - correct answers 2 ice melts in a glass of lemonade, cooling the lemonade. If the ice cubes are defined as the system, what are the signs of DELTAS AND DELTASsurr? - correct answers Positive,negative If DELTAG for a redox reaction is positive, which of the following statements is true? - correct answers E is negative Cesium has a half life of 30 years. How much of a 240g sample will remain after 90 years? - correct answers 30 g Which of the following has the largest entropy (S)? - correct answers F2 (g) Since 2014, the water in Flint, Michigan has been undrinkable due to high amounts of lead ions (Pb2+) in the water supply. Ksp (PbCl2) = 2.4 x 10-4 Ksp (PbCo3) = 3.3 x 10^-14 Ksp (Pbl2) = 1.4 x 10-8 Given the Ksp values above, if your goal is to remove as much lead as possible via precipitation with as little salt as possible, would you add: - correct answers C. Na2CO3 The value of Keq for the equilibrium H2(g)+I2(g) - 2HI(g) is 890 at 25 degrees Celsius. What is the value of Keq for the equilibrium below? 1/2 H2(g)+ 1/2I2 (g) - HI(g) - correct answers 29.8 What is the pKa of this acid? - correct answers 5 What biologically relevant condition would HA/A- make the best buffer? - correct answers Urine (pH 4.8-5.2) How much 0.1 M NaOH do we need to add for [HA]=[A-]? - correct answers 12.5 mL Which of the following statements are true regarding HA? I. HA is a strong acid II. HA is a weak acid III. HA is polyprotic IV. At the equivalence point [H+]=[OH-] - correct answers II. By reading this question, the entropy of the universe has - correct answers Increased Which of the following is on an absolute scale and NOT a relative scale? - correct answers S The graphs above represent concentration vs. reaction progress for the following equilibrium: I2 (g) + Cl2(g) - 2lCl (g) + heat Identify the graph that best represents each of the following stresses and shifts. Adding I2: - correct answers A Removing Cl2: - correct answers B Increasing temperature: - correct answers B Colligative properties depend on: - correct answers The number of solute particles Which of the following conditions allows the spontaneous emergence of complexity? - correct answers DELTAsys 0, DELTASsurr 0, DELTASuniv 0 Which of the following molecules will form hydrogen bonds with itself? - correct answers None of the above Your goal is to make as high as positive voltage galvanic cell as possible. Given the table to the right, which cell would you generate? - correct answers K (s) | K+ (aq) || Ag+ (aq) | Ag (s) For the table above, which of the following statements is false? - correct answers Cu(s) will transfer electrons to Al3+ The fully protonated form of cysteine and the pKa for the thiol side chain as well as the C and the N terminus are given below: If cysteine is in pancreatic fluid (pH= 8.5), which of the below structures would be the dominant form in that solution? - correct answers B Which of the following results in an increase in entropy? I. I2 (s) -- I2 (g) II. 2I (g) -- I2 III. 2NH3 (g) -- N2(g) + 3H2(g) IV. Mg2+ (aq) + 2OH-(a) - Mg(OH)2 (s) - correct answers I and III only What is the rate law of the above reaction? - correct answers rate= k[A]2[B] Assuming the answer to the previous question was e, what are the units on k? - correct answers M-2s-1 Consider the following multistep equilibria: N2(g) + O2 (g) - 2NO (g) 2NO(g) + O2(g) - 2NO2 (g) - correct answers C. NO For the first equilibrium reaction (N2 (g)+O2(g)...) - correct answers kfwdkrev What is the value for the equilibrium constant for the oxidation of N2 by O2 to create NO2? - correct answers 6.9x10^-13 For which of the following acids could you conf