CHEM 101 WINTER 08-09 FINAL EXAM On the answer sheet (Scantron) write you name, student ID number, and recitation section number. Choose the best (most correct) answer for each question and enter it on your answer sheet. Avogadro s Number: 6.022 10 23 mol -1 P 1 V 1 / n 1 T 1 = P 2 V 2 / n 2 T 2 Speed of Light: c = 3.00 x 10 8 m s -1 Planck s Constant: h = 6.626 x 10-34 J s PV = nrt d = PM / RT Rydberg Constant: R = 2.179 x 10-18 J R = 0.0821 L atm mol -1 K -1 E = hc/λ = hυ 1 atm = 760 Torr = 760 mm Hg q = m c T Specific Heat of Water = 4.184 J g -1 C -1 1. Please chose the letter a as your answer for this question. 2. Which of the following is a chemical property of iron? a. Iron conducts electricity. b. Iron conducts heat. c. Iron melts at 1535 C. d. Iron can be bent into shapes. e. Iron rusts on exposure to water and oxygen. 3. Which of the following compounds can be dissolved in water to give a solution that conducts electricity? a. CCl 4 (carbon tetrachloride) b. (CH 3 ) 2 CHOH (isopropyl alcohol) c. C 12 H 22 O 11 (sucrose) d. C 6 H 14 (hexane) e. Ba(NO 3 ) 2 (barium nitrate) 4. Which of the following is not a metal? a. nickel (Ni, atomic number 28) b. lithium (Li, atomic number 3) c. phosphorus (P, atomic number 15) d. uranium (U, atomic number 92) e. calcium (Ca, atomic number 20) 1
5. When an atom loses electrons, are formed. a. neutrons b. nuclei c. ions d. protons e. alpha particles 6. Which of the following represent a pair of isotopes? Cl Ar O F Ar I. II. III. IV. V. a. I and III b. I and II c. I and IV d. II and V e. III and IV 7. An element that has 32 protons, 32 electrons, and 52 neutrons has an approximate atomic weight of: a. 64 amu. b. 32 amu. c. 52 amu. d. 116 amu. e. 84 amu. 8. Three elements that are likely to have similar chemical and physical properties are: a. B, C, Si b. H, He, Ne c. Pb, Bi, Po d. Cu, Ag, Au e. Ca, Co, Cr 9. Which formula and name combination is incorrect? a. N 2 O 3 and dinitrogen trioxide b. P 4 O 10 and tetraphosphorus decaoxide c. AsF 5 and arsenic pentafluoride d. SF 6 and sulfur heptafluoride e. SeCl 4 and selenium tetrachloride 2
10. What is the correct general formula for a straight-chain alkyne? a. C n H 2n b. C n H n c. C n H 2n+2 d. C n H n+2 e. C n H 2n 2 11. Find the correct combination of protons and electrons below for the magnesium ion. a. 12 protons and 10 electrons b. 24 protons and 22 electrons c. 12 protons and 12 electrons d. 12 protons and 14 electrons e. 24 protons and 24 electrons 12. Determine the number of molecules in a drop of water that has a mass of 0.050 g. a. 6.50 10 26 molecules b. 5.02 10 21 molecules c. 5.42 10 23 molecules d. 1.67 10 21 molecules e. 2.17 10 26 molecules 13. Which statement regarding the complete combustion of a carbon compound is correct? a. Carbon dioxide and water are consumed in the reaction and must be shown in the balanced equation. b. Heat is produced in the reaction and must be shown in the balanced equation. c. The carbon compound is consumed in the reaction but need not be shown in the balanced equation. d. Balancing the equation requires knowing whether the products are gases or liquids. e. Oxygen is consumed in the reaction and must be shown in the balanced equation. 14. For the reaction given below, how many moles of aluminum will react if 15 moles of Br 2 react and 10 moles of AlBr 3 are produced? 2 Al + 3 Br 2 2 AlBr 3 a. 10 b. 8 c. 16 d. 4 e. 40 3
15. Classify the following reaction. 2 Al(s) + 3 CuSO 4 (aq) Al 2 (SO 4 ) 3 (aq) + 3 Cu(s) a. exchange b. decomposition c. combustion d. combination e. displacement 16. The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I Ni(ClO 4 ) 2 + II K 2 S III KClO 4 + IV NiS I II III IV a. 1 2 2 1 b. 1 2 1 1 c. 2 1 1 2 d. 1 1 2 1 e. 1 1 1 2 17. What is the net ionic equation for the reaction of Ba(NO 3 ) 2 with Na 2 SO 4? a. Ba 2+ 2 + SO 4 BaSO 4 b. Na 2+ + 2NO 3 Na(NO 3 ) 2 c. 2Ba + 2 + SO 4 Ba 2 SO 4 d. Ba + + SO 4 BaSO 4 e. Na + + NO 3 NaNO 3 18. What is the correct formula for the hydronium ion? a. H 3 O + b. H c. H + d. OH e. NH 4 + 19. What is the reducing agent in the reaction below? Zn(s) + CuSO 4 (aq) ZnSO 4 (aq) + Cu(s) 2 a. SO 4 b. Zn 2+ c. CuSO 4 d. Cu 2+ e. Zn 4
20. A 64.00 ml sample of 0.250 M HBr is to be exactly neutralized with 0.125 M KOH. How many milliliters of KOH will be required? a. 16.0 ml b. 32.0 ml c. 8.01 ml d. 64.1 ml e. 128 ml 21. Heating a 200. g sample of iron (specific heat = 0.451 J g 1 C 1 ) raised its temperature from 25.0 C to 52.0 C. How much energy was required to heat the sample? a. 2.41 J b. 564 J c. 1218 J d. 2435 J e. 0.414 J 22. What is the molar heat capacity of aluminum (specific heat of aluminum = 0.902 J g 1 C 1 )? a. 29.3 J mol 1 C 1 b. 1.5 10 25 J mol 1 C 1 c. 120 J mol 1 C 1 d. 24.3 J mol 1 C 1 e. 0.034 J mol 1 C 1 23. What is the enthalpy change for the combustion of 5.80 g C 4 H 10 in excess oxygen? C 4 H 10 (g) + 13/2O 2 (g) 4CO 2 (g) + 5H 2 O(g) H = 1895 kj a. 190 kj b. 23200 kj c. 401 kj d. 8960 kj e. 32.7 kj 24. An endothermic chemical reaction occurs when a. stronger bonds are formed and weaker bonds are broken. b. no bonds are broken. c. many bonds are formed. d. the energy of bonds breaking is less than the energy of bonds formed. e. the energy of bonds breaking is greater than the energy of bonds formed. 5
25. A 1.00 mole sample of CH 4 reacts completely in a calorimeter having a heat capacity of 3915 J/ C. The calorimeter contains 1270 g of water. Determine the temperature increase of the calorimeter. CH 4 (g) + 2O 2 (g) 2H 2 O(g) + CO 2 (g) H = 802.3 kj a. 7.56 C b. 4.35 10 3 C c. 86.9 C d. 31.6 C e. 10.2 C 26. Calculate the standard enthalpy change, H, for the following reaction Pb(Cl) 2 (s) + Cl 2 (g) PbCl 4 (l) using the information given below: Pb (s) + Cl 2 (g) PbCl 2 (s) H = -359.4 kj a. +30.1 kj b. 131.1 kj c. + 398.4 kj d. 30.1 kj e. + 131.1kJ Pb (s) + 2 Cl 2 (g) PbCl 4 (l) H = -329.3 kj 27. The standard enthalpies of formation for several substances are given below: CO (g) 110.5 kj/mol CO 2 (g) 393.5 kj/mol H 2 O (g) 241.8 kj/mol H 2 O (l) 285.8 kj/mol H 2 O 2 (l) 187.8 kj/mol CH 3 OH (g) 200.7 kj/mol C 3 H 8 (g) 103.8 kj/mol CH 3 OH (l) 238.7 kj/mol Determine the H for the reaction below. C 3 H 8 (g) + 5 O 2 (g) a. 2220 kj b. 575 kj c. +575 kj d. 782. kj e. 2322 kj 3 CO 2 (g) + 4 H 2 O (l) 6
28. Light has a wavelength of 532 nm. What is its frequency? a. 5.64 10 14 Hz b. 1.48 10 15 Hz c. 6.76 10 4 Hz d. 1.48 10 6 Hz e. 1.48 10 2 Hz 29. Determine the energy of a photon that has a wavelength of 532 nm. a. 1.27 10 48 J b. 3.74 10 19 J c. 1.04 10 10 J d. 7.87 10 47 J e. 1.16 10 27 J 30. Which azimuthal quantum numbers can exist for n = 3? a. l = 0, 1, 2, 3, 4 b. l = 0, 1, 2 c. l = 0 d. l = 0, 1, 2, 3 e. l = 0, 1 31. How many orbitals are contained in each d subshell? a. 5 b. 3 c. 10 d. 2 e. 14 32. Which of the following corresponds to the electron configuration of a noble gas? a. 1s 2 2s 2 2p 4 b. 1s 2 2s 2 2p 6 3s 2 3p 6 c. 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 2 d. 1s 2 2s 2 e. 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 3 33. Atoms and ions that have identical electron configurations are referred to as being a. paramagnetic. b. ferromagnetic. c. diamagnetic. d. isoelectronic. e. lanthanides. 7
34. How many electrons will be in the correctly drawn Lewis Structure for the perchlorate anion, ClO? a. 26 b. 20 c. 24 d. 32 e. 22 35. Assume that all of the following are straight-chain hydrocarbons. Which compound will contain a double bond? a. C 3 H 4 b. C 6 H 14 c. C 9 H 16 d. C 2 H 6 e. C 8 H 16 36. In organic compounds, with which of the following types of bonds is cis-trans isomerism associated? a. carbon-oxygen single bonds b. carbon-carbon triple bonds c. carbon-carbon double bonds d. carbon-oxygen double bonds e. carbon-carbon single bonds 37. Of the following elements, which is the least electronegative? a. strontium, Sr, atomic no. 38 b. potassium, K, atomic no. 19 c. osmium, Os, atomic no. 76 d. calcium, Ca, atomic no. 20 e. cesium, Cs, atomic no. 55 38. Which statement properly describes the formal charges on the atoms in PO? a. +1 on oxygen, 3 on phosphorus b. +1 on oxygen, 1 on phosphorus c. 1 on oxygen, +1 on phosphorus d. 2 on oxygen, +5 on phosphorus e. 1 on oxygen, +4 on phosphorus 8
39. Construct correct Lewis dot structures for the three molecules below. Which compound(s) exceed(s) the octet rule? PF 3 SF 4 BeF 2 I II III a. I b. II c. III d. I, II, and II e. II and III 40. VSEPR Theory attempts to electron-pair. a. maximize, repulsions b. minimize, collisions c. minimize, repulsions d. maximize, attractions e. eliminate, attractions 41. Using VSEPR Theory, predict the electron-pair geometry for two, four, and six electron-pairs, respectively. a. tetrahedral, triangular bipyramidal, octahedral b. linear, tetrahedral, hexagonal c. linear, triangular pyramidal, octahedral d. linear, tetrahedral, octahedral e. angular, triangular pyramidal,octahedral 42. For the tetramethyl ammonium ion, [N(CH 3 ) 4 ] +, use VSEPR Theory to predict the electron-pair geometry, the molecular geometry, and the C-N-C bond angle, respectively. a. triangular bipyramidal, tetrahedral 90 b. tetrahedral, tetrahedral, 109.5 c. tetrahedral, triangular pyramidal 109.5 d. square planar, square planar, 90 e. tetrahedral, square planar, 109.5 9
43. Which of the following molecules is/are polar? I. PF 5 II. SF 4 III. SiF 4 IV. XeF 4 a. II only b. I and II c. II, III, and IV d. I, II, and III e. I only 44. What is the major type of force that must be overcome to allow each of the processes below, in the order I to IV? I. the evaporation of liquid CH 3 CH 2 OH II. the vaporization of liquid CHCl 3 III. the sublimation of solid I 2 IV. the boiling of liquid C 5 H 12 a. hydrogen bonding, London (dispersion) forces, dipole-dipole, dipole-dipole b. dipole-dipole, dipole-dipole, London (dispersion) forces, London (dispersion) forces c. London (dispersion) forces, London (dispersion) forces, London (dispersion) forces, London (dispersion) forces d. London (dispersion) forces, covalent bonding, dipole-dipole, dipole-dipole e. hydrogen bonding, dipole-dipole, London (dispersion) forces, London (dispersion) forces 45. Determine the height (in mm) of a column of bromine in a barometer at a pressure of 1520 mm Hg. The densities of mercury and bromine are 13.546 and 3.119 g/cm 3, respectively. a. 6.60 10 3 b. 0.00571 c. 1.75 10 2 d. 42.3 e. 4.34 46. Calculate the number of moles of boron trifluoride gas that occupy 2.80 L at STP. a. 0.330 b. 0.125 c. 2.40 10 4 d. 3.10 e. 3.30 10 2 10
47. What is the density (in g/l) of methane, CH 4, at 50 C and 0.50 atm of pressure? a. 9.9 b. 6.2 10 3 c. 0.30 d. 4.9 10 2 e. 1.2 48. A mixture of He, Ne and Ar has a total pressure of 0.60 atm and contains 0.45 mol He, 0.65 mol Ne and 0.25 mol Ar. What is the partial pressure (in atm) of each gas, respectively? He Ne Ar a. 1.5.85 1.5 b. 2.7 1.6 4.2 c. 0.20 0.29 0.11 d. 0.44 0.75 0.28 e. 0.095 0.16 0.060 49. Under what conditions do real gases most closely approximate the behavior of ideal gases? a. standard temperature and pressure b. low pressure and low temperature c. low pressure and high temperature d. high pressure and high temperature e. high pressure and low temperature 50. Which of the following is the correct sequence for the three principle types of reactions which make up a free-radical process? a. initiation, substitution, termination b. elimination, termination, substitution c. initiation, elimination, termination d. substitution, elimination, termination e. initiation, propagation, termination 51. Which of the following is a greenhouse gas? a. carbon dioxide b. methane c. water vapor d. ozone e. all of the above 11