CHM 1045-All Sections Exam 2 Practice Fall Unit 2 Stoichiometry, Aqueous Solutions, & Thermo Chapters 3-6

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1 CHM 1045-All Sections Exam 2 Practice Fall 2013 Unit 2 Stoichiometry, Aqueous Solutions, & Thermo Chapters 3-6 ======================================================================= 1. Calculate the concentration of an oxalic acid (H 2 C 2 O 4 ) solution when 73.4 ml of water is added to 31.5 ml of a 3.03 M oxalic acid solution? A M B M C M D M E M 2. IF 5 liquid can be produced according to the following reaction. 2 MnI 2 (s) + 13 F 2 (g) > 2 MnF 3 (s) + 4 IF 5 (l) Calculate the amount of MnI 2 that would be required to react in excess fluorine to produce g of IF 5 if the percent yield for the reaction is 56%. A g B g C g D g E g 3. How much water will you add to 36.8 ml of a 6.25 M NaNO 3 solution to create a M NaNO 3 solution? A ml B ml C ml D ml E ml 4. Identify the oxidizing agent in the following reaction. 3 IO 3 (aq) + 2 MnO 4 (aq) + H 2 O (l) > 2 MnO 2 (s) + 3 IO 4 (aq) + 2 OH (aq) A. I B. IO 3 C. Mn D. MnO 4 E. IO 4 Page 1

2 5. Aluminum chloride, AlCl 3, is made by treating scrap aluminum with chlorine according to the following reaction. 2 Al (s) + 3 Cl 2 (g) > 2 AlCl 3 (s) How much aluminum chloride can be produced if you react 3.62 g of aluminum with 5.56 g of Cl 2 (g)? A g AlCl 3 B g AlCl 3 C g AlCl 3 D g AlCl 3 E g AlCl 3 6. Which of the following mixtures would produce a precipitate? A. NaCl and KCH 3 CO 2 B. potassium acetate and mercury(i) nitrate C. LiBr and Fe(NO 3 ) 2 D. hydroiodic acid and AgClO 4 E. Pb(NO 3 ) 2 and NaClO 3 7. What is the oxidation number in chromium in CrO 4 3 A. +2 B. +3 C. +5 D. +6 E Calculate the molarity of chloride ions in solution if you were to mix 7.92 g of aluminum chloride, AlCl 3, in enough water to make ml of solution A M B M C M D M E M 9. Potassium permanganate, KMnO 4 can be used to titrate oxalic acid, H 2 C 2 O 4 acccording to the following net ionic equation. The solution will turn pale pink when all of the oxalic acid has reacted. What is the concentration of an oxalic acid solution if it requires ml of M potassium permanganate to completely react with ml of oxalic acid? 5 H 2 C 2 O 4 (aq) + 2 MnO 4 (aq) + 6H + (aq) > 10 CO 2 (g) + 2 Mn 2+ (aq) + 8 H 2 O (l) A M B M C M D M E M Page 2

3 10. Benzene is a starting material in the synthesis of nylon fibers and polystyrene (styrofoam). Its specific heat capacity is 1.74 J/gK. If 14.3 kj of energy is absorbed by a 302 g sample of benzene at 25.0 C, what is its final temperature? A. 2.2 C B C C C D. 2.2 C E C 11. Calculate the energy change in a system in which kj of heat is given off at atm pressure and the volume changes from L to L. A kj B kj C kj D kJ E kj 12. Calculate the energy of a photon emitted by a hydrogen atom when the electron falls from the n=15 energy level to the n=5 energy level. A x 10-4 J B x 10 3 J C x J D x J E x J 13. Consider the reaction shown below: A + 3 B > 2 C H = kj What is H for the following reaction? 2/3 C > 1/3 A + B H =? A kj B kj C kj D kj E kj 14. Calculate the kinetic energy of an electron moving at 6.85 x 10 6 ms -1. The mass of an electron is 9.11 x kg. A x J B x J C x J D x J E x J Page 3

4 15. Which of the following would be a NON-electrolyte? A. hydrochloric acid B. KCl C. LiOH D. HClO 3 E. CH 3 CH 2 OH 16. Calculate the amount of heat released in the following reaction when g of carbon dioxide is produced in the reaction. 2 CH 3 OH (l) + 3 O 2 (g) 2 CO 2 (g) + 4 H 2 O(l) H = kj A kj B kj C kj D kj E kj 17. Sulfuric acid dissolves aluminum metal according to the following reaction: 2 Al(s) + 3 H 2 SO 4 (aq) > Al 2 (SO 4 ) 3 (aq) + 3 H 2 Calculate the volume of 1.06 M H 2 SO 4 that would be required to completely dissolve a g block of aluminum. A ml B ml C ml D ml E ml 18. What is the wavelength of an FM radio station that broadcasts at MHz? A x m B x10 6 m C m D x m E x m 19. For which of the following reactions is H = H f, the heat of formation? A. i only B. ii only C. iii only D. i and ii E. i and iii i. C (s) + 2 F 2 (g) > CF 4 (g) H = kj ii. H(g) + Br (g) > HBr (g) H = kj iii. 2 C(s) + H 2 (g) + 3 Cl 2 (g) > 2 CHCl 3 (g) H = Page 4

5 20. Consider the following equation for the combustion of acetone, the main ingredient in nail polish remover. C 3 H 6 O(l) + 4 O 2 (g) > 3 CO 2 (g) + 3 H 2 O (g) H rxn = 1790 kj Calculate the amount of heat that would be released if ml of acetone were burned in excess oxygen. The density of acetone is g/ml A kj B kj C kj D kj E kj 21. Which of the following reactions is a redox reaction? The equations may not be balanced. A. SiCl 4 (l) + 2 H 2 O (l) 4 HCl (aq) + SiO 2 (s) B. Cr 2 O 7 2 (aq) + 2 OH (aq) 2 CrO 4 2 (aq) + H 2 O (l) C. O 3 (g) + NO (g) O 2 (g) + NO 2 (g) D. HCl (g) + NH 3 (g) NH 4 Cl (s) E. 2 CH 3 CO 2 H (aq) + Al(OH) 3 (aq) Al(CH 3 CO 2 ) H 2 O 22. A 5.00 g chunk of hot metal is plunged into an insulated beaker containing g of water at C. The metal loses kj of energy. What is the final temperature of the water? A C B C C C D C E C 23. Given the heats of formation for NH 3 (g), NO(g), and H 2 O(g) are kj, kj, and kj respectively, calculate H for the reaction below. 4 NO (g) + 6 H 2 O (g) 4 NH 3 (g) +5 O 2 (g) A kj B. 106 kj C kj D kj E. 905 kj 24. Calculate the amount of M phosphoric acid, H 3 PO 4, that would be required to completely neutralize ml of M magnesium hydroxide. A ml B ml C ml D ml E ml Page 5

6 25. Use the following equations C 6 H 4 O 2 (aq) + H 2 (g) C 6 H 4 (OH) 2 (aq) H = kj H 2 (g) + 1/2 O 2 (g) H 2 O (g) H 2 (g) + O 2 (g) H 2 O 2 (aq) H = 241.8kJ H = kj H 2 O (l) H 2 O (g) H = kJ to calculate H for the reaction below. C 6 H 4 (OH) 2 (aq) + H 2 O 2 (aq) C 6 H 4 O 2 (aq) + 2 H 2 O (g) A kj B kj C kj D kj E kj 26. What is the original molarity of an HNO 3 solution if ml of this solution is mixed with enough water to make ml of a M dilute nitric acid solution? A M B M C M D M E M Page 6

7 Answer Key for Test F13 Practice Exam, 10/16/13 No. in No. on Q-Bank Test Correct Answer C E A D E D C E C B A E B D E A A C A E C E C B E B Page 1

8 Statistics for Test F13 Practice Exam. Total questions: 26 Key Word Total Difficulty Level Total None Total None 6 None 0 Essay 0 LO 3.6 Emp formula 0 Easy 10 Short Answer 0 LO 3.7 Molecular formfrom Emp 0 Moderate 8 Fill in Blank 0 LO 3.8 Limiting Reations 0 Hard 3 Matching 0 LO 3.9 % yield 0 Max Diff 5 Identification 0 LO. 4.1 electrolytes and non-elec 0 Max Difficulty 0 True or False 0 LO 4.2 ppt rxns 1 Medium 0 Multiple Choice 26 LO 4.3 net ionic rxns 1 Difficult 0 Matching Question 0 LO 4.4 ID SA 4 LO 4.5 BL theory of A/B 1 LO 4.6 Balance A/B rxns 1 LO 4.7 Oxidation nos 1 LO 4.8 ID redox rxns 1 LO 4.9 Activity Series 0 LO 4.10 Bal simple redox rxn 0 LO 4.11 Molarity 2 LO 4.12 Dilution 2 LO 4.13 Gravimetric Anal Titration 0 LO 10.1 Pressure Units 0 LO 10.2 Ideal Gas Law 1 LO 10.3 Daltons Law 1 LO 10.4 Gas Laws and Stoich. 0 LO 10.5 KMT 0 LO 10.6 Graham' Law 0 LO 10.7 Real Gases 0 LO 5.1 E units 0 LO 5.2 H, E, &w 0 LO 5.3 Enthalpy 1 LO 5.4 Calorimetry 2 LO 5.5 Hess's Law 0 LO 5.6 Heats of Formation 0 LO 5.7 Heats of formation relate c=l v Bohr atom QNs Orbitals e- config unpaired e config anomolies atomic radii trends vs. convig discuss ion charge re octet polarity of bonds Lewis Struc Resonance 0 L.O L.O L.O L.O L.O L.O L.O.4.4 0