Chemistry 12 Name Exam I Form A Section February 7, 2001 Student No.

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1 Chemistry 12 Name Exam I Form A Section February 7, 2001 Student No. IMPRTANT: n the scantron (answer sheet), you MUST clearly fill your name, your student number, section number, and test form (white cover = test form A; yellow cover = test form B). Use a #2 pencil. CHEM 12, Exam I February 7, 2001 Form A 1. What is the correct IUPAC name of the following alkane? -C-CH 2 -CH-CH 2 - CH-CH 2 - a. 4-isobutyl-2,2-methylhexane b. 2,3-diethyl-5,5-dimethylhexane c. 4-ethyl-2,2,5-trimethylheptane d. 4-ethyl-2,2-dimethyloctane e. 4-ethyl-3,6,6-trimethylheptane There are 26 questions on this exam. Check that you have done all of the problems and filled in the first 26 bubbles on the scantron. The maximum score on this exam is 20 points. 2. Which of the following molecules would you expect to react with Br 2 in an addition reaction? Exam policy Calculators with text-programmable memory are not allowed. Relevant data and formulas, including the periodic table, are attached at the end of this exam. Your grade will be based only on what is on the scantron form. The answer key will be posted on the web after the exam (under "News"). I) Cl Cl II) Hints III) IV) As you read the question, underline or circle key words to highlight them for yourself. Avoid errors from "mis-reading" the question. There is no penalty for guessing. a. I, II, and III b. II and III c. I and IV d. IV e. all of the molecules 1 2

2 3. According to the following balanced chemical reaction, how much of CaCl 2 must be combined with an excess of AgN 3 to produce 100 g of AgCl? a g b g c g d g e. 100 g CaCl 2 (aq) + 2 AgN 3 (aq) Ca(N 3) 2 (aq) + 2 AgCl (s) 4. What is the weight percentage of nitrogen in urea [(NH 2 ) 2 C]? a. 46.7% b. 31.8% c. 23.3% d. 48.3% e. 63.6% 5. Which of the following is an isomer of pentane? a. 2-methylpropane b. 3-ethylpentane c. 2,2-dimethylpropane d. 2-pentene e. 2,2-dimethylbutane 6. How many protons, neutrons, and electrons are present in the following ion? a. p = 16, n = 15, e = 12 b. p = 15, n = 16, e = 18 c. p = 15, n = 16, e = 12 d. p = 15, n = 16, e = 15 e. p = 16, n = 15, e = P 7. A Chem 12 student completely combusts exactly one mole of ascorbic acid (C 6H 8 6), commonly known as vitamin C, in a bomb calorimetry experiment. What is the correct coefficient of water in the complete combustion reaction of 1 mole of vitamin C? a. 8 b. 6 c. 5 d. 4 e Which of the following names does not follow the official (IUPAC) organic nomenclature rules? a. 2-ethylpropane b. 3-methylhexane c. 3-ethylnonane d. 2-methylpropane e. 2,3-dimethylpentane 9. How many structural isomers are there for hexane? a. 1 b. 2 c. 3 d. 4 e Which of the following formula name combinations are correct? I. NH 4Br ammonium bromide II. Ca 2 calcium oxide III. KC 3 potassium carbonate IV. MgS 4 magnesium sulfate a. all of the above. b. I, II, and IV only c. I, III, and IV only d. II and III only e. I and IV only

3 11. Assuming that all energy from glucose (C 6H 12 6) is converted to heat (as shown in the equation below), if a person metabolizes 18 kg of glucose a month, how much heat will her body produce? 14. Which of the following reactions illustrates a method for the formation of an ester? C 6H 12 6 (s) (g) 6C 2 (g) + 6H 2 (l) H = kj a. 282 kj b kj c. 309 kj d x 10 5 kj e x 10 5 kj 12. The molecule below (alanine) is an amino acid. It may polymerize to form a polyalanine. If the polyalanine contains amide functional groups, which of the following statements is true? a. b. c. d. + NaH H 3 C H + H 3 C CH 2 H H 3 C CH 2 H H + H 3 C CH 2 H + H 3 C NH 2 Na H 3 C H + CH 2 N H + H 2 + H 2 + H 2 a. Alanine polymerized through an addition reaction. b. Alanine polymerized through a condensation reaction. c. Alanine polymerized through a pollination reaction. d. Alanine polymerized through a reduction-oxidation reaction. e. Alanine polymerized through an acid-base reaction. 13. Calcium nitrate (0.015 g) was dissolved in 300 ml of water. What is the molar concentration of N 3 ions? a. 4.6 x 10-4 M b. 1.0 x 10-1 M c. 3.0 x10-4 M d. 1.8 x10-4 M e. 6.1 x 10-4 M NH 2 H e. none of the above 15. If each of the following organic compounds is an alkane, which one is cyclic? a. C 3 H 8 b. C 22H 46 c. C 7H 14 d. C 12H 26 e. C 8H What is the molarity of NaCl in a solution made by mixing 25.0 ml of M NaCl with 50.0 ml of M NaCl? a M b M c M d M e M 5 6

4 17. Fructose has weight percentage compositions of 40.0% carbon, 53.3% oxygen, and 6.7% hydrogen. Which of the following is a possible molecular formula for fructose? a. C 5H 5 8 b. CH 4 c. C 22H d. C 6H 12 6 e. none of the above 18. Consider the following reactions: AgN 3 (aq) + Zn (s) Ag (s) + Zn(N 3) 2 (aq) Zn(N 3 ) 2 (aq) + Co (s) No reaction AgN 3 (aq) + Co (s) Co(N 3) 2 (aq) + Ag (s) Which is the correct order of increasing activity for these metals? a. Ag < Zn < Co b. Co < Ag < Zn c. Co < Zn < Ag d. Ag < Co < Zn e. Zn < Ag < Co The neutralization reaction between nitric acid and sodium hydroxide produces water and sodium nitrate. Nitric acid (63 g) and sodium hydroxide (60 g) are mixed. Which one of the following is a true statement? a. All of the nitric acid will be consumed. b. All of the sodium hydroxide will be consumed. c. There will be nitric acid left unreacted. d. Exactly 27 g of water will form. e. The reaction mixture will feel cold 20. There are four oxyanions containing chlorine and oxygen (Cl, Cl 2, Cl 3, and Cl 4 ). What is the name of the following acid? HCl 4 a. hydrochlorous acid b. perchloric acid c. hydrochloric acid d. hypochlorous acid e. chloric acid 21. When aqueous solutions of LiCl (aq) and AgN 3 (aq) are mixed, an insoluble salt forms. Which of the following is the net ionic equation that describes this reaction? a. LiCl (aq) + AgN 3 (aq) AgCl (s) + LiN 3 (aq) b. Cl (aq) + Ag + (aq) AgCl (s) c. Li + (aq) + Cl (aq) + Ag + (aq) + N 3 (aq) AgCl (s) + Li + (aq) + N 3 (aq) d. Li + (aq) + N 3 (aq) LiN 3 (s) e. Li + (aq) + Cl (aq) + Ag + (aq) + N 3 (aq) Ag + + Cl (aq) + LiN 3 (s) 22. Given the reaction below, which one of the following statements is false? C 3H 8 (g) (g) 3C 2 (g) + 4H 2 (l) H = kj a. The enthalpy of the reactants is greater than the enthalpy of the products. b. The combustion of propane is exothermic. c. If 3 moles of C 2 (g) and 4 moles of H 2 (l) react to form propane gas and oxygen gas, 2220 kj of heat will be consumed. d. The reactants must be provided with 4440 kj of energy to produce 6 moles of carbon dioxide. e. This is an example of a reaction where the energy of chemical bonds is converted to heat. 7 8

5 23. Serine, the molecule shown below, contains which of the following functional groups? 26. Which of the following statements regarding enthalpy are true? NH 2 CH C H CH 2 H I. Enthalpy is an extensive property. II. The enthalpy change for a reaction is equal in magnitude but opposite in sign to the enthalpy change for the reverse reaction. III. The enthalpy change for a reaction depends on the state of the reactants and products. IV. Under constant pressure, the change in enthalpy of a system equals the amount of heat gained or lost by the surroundings. V. Enthalpy is a state function. a. amide, alcohol, ester b. amide, carboxylic acid, alcohol c. amide, ester, carboxylic acid d. amine, alcohol, carboxylic acid e. amine, ester, alcohol a. all of the above. b. I, II, III, and IV only c. III, IV, and V only d. II, III, IV, and V only e. I, II, III, and V only 24. In which of the pairs listed below both compounds are strong electrolytes? I. CH and HCl 4 II. HF and NH 3 III. NaCl and Sr(H) 2 IV. HCl and C 6H 13H END F EXAM. a. III only b. I and II only c. II and IV only d. I and III only e. II and III only 25. Hydrocarbons with formula C 4H 8 can exist as cycloalkanes or alkenes. Considering all possibilities (all ring sizes and branching alternatives) that satisfy the valence rules, how many isomers (structural and geometrical) are there for C 4H 8? a. 2 b. 3 c. 4 d. 5 e

6 PERIDIC TABLE of the ELEMENTS (2001) Answer key Chem 12 Exam 1 MAIN GRUPS MAIN GRUPS 1A 1 1 H 2A 3A 4A 5A 6A Li Na K Rb Cs Fr [223] 4 Be Mg Ca Sr Ba Ra [226] 3B 3 21 Sc Y La* Ac** [227] * LANTHANIDS ** ACTINIDS 4B 4 22 Ti Zr Hf Rf [261] 5B 5 23 V Nb Ta Db [262] 58 Ce Th B 6 24 Cr Mo W Sg [266] 59 Pr Pa TRANSITIN METALS 7B 7 25 Mn Tc [98] 75 Re Bh [264] 60 Nd U B 8 26 Fe Ru s Hs [265] 61 Pm [145] 93 Np [237] 8B 9 27 Co Rh Ir Mt [268] 62 Sm Pu [244] 8B Ni Pd Pt [269] 63 Eu Am [243] 11 1B Cu Ag Au [272] 64 Gd Cm [247] 2B Zn Cd Hg [277] 65 Tb Bk [247] 5 B Al Ga In Tl Dy Cf [251] 6 C Si Ge Sn Pb [285] 67 Ho Es [252] 7 N P As Sb Bi Er Fm [257] S Se Te Po [209] 116 [289] 69 Tm Md [258] 7A 17 9 F Cl Br I At [210] 70 Yb No [259] 8A 18 2 He Ne Ar Kr Xe Rn [222] 118 [293] 71 Lu Lr [262] February 7, 2001 Form A 1. C 2. B 3. B 4. A 5. C 6. B 7. D 8. A 9. E 10. E 11. D 12. B 13. E 14. C 15. C 16. A 17. D 18. D 19. A 20. B 21. B 22. D 23. D 24. A 25. E 26. A 12