CHEM Practice Final Exam 2014

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Elijah Washington
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1 Final Exam 2 1. Which of the following would you expect to have the highest boiling point? a. I 2 b. F 2 c. Cl 2 d. Br 2 e. All of the above have the same boiling point. 2. Which of the compounds below is an example of a network solid? a. S 8 (s) b. C 25 H 52 (s) c. MgO(s) d. SiO 2 (s) e. NaCl(s) 3. Mixing a metal with other substances to modify its properties is known as. a. charging b. refining c. roasting d. alloying e. smelting 4. The energy of the light emitted when a hydrogen electron goes from n = 3 to n = 1 is what fraction of its ground-state ionization energy? a. 1/9 b. 1/3 c. 10/9 d. 8/9 e. 2/3 5. Which of the following statements is true? a. There are 3 e g orbitals. b. oct is proportional to the crystal field strength of the metal ion. c. All five d orbitals increase their energy levels the same amount for a metal surrounded by ligands in an octahedral crystal field. d. Because the ligands approach the metal ion from different directions, they affect different d orbitals in different ways. e. The t 2g orbitals are higher in energy than the e g orbitals. 6. Which one of the following statements is false? a. Diamagnetic metal ions cannot have an odd number of electrons. b. In high spin octahedral complexes, oct is less than the electron pairing energy. c. Low spin complexes can be paramagnetic. d. Paramagnetic metal ions must have an odd number of electrons. e. Low spin complexes contain strong field ligands. 1

2 7. How many and bonds does C have in HCN? a. 1 and 1 b. 1 and 2 c. 2 and 2 d. 3 and 1 e. 2 and 1 8. How many electrons can be described by the quantum numbers n = 2, l = 2, m l = 1? a. 0 b. 6 c. 10 d. 2 e Which of the following complexes shows geometrical isomerism? a. [Co(NH 3 ) 5 Cl]Cl 2 b. [Co(NH 3 ) 5 Cl]SO 4 c. [Co(NH 3 ) 6 ]Cl 3 d. K[Co(NH 3 ) 2 Cl 4 ] e. none of these 10. What is the hybridization at the boron atom in gaseous BBr 3? a. sp 2 b. sp 3 c. sp d. sp 3 d 2 e. sp 3 d 11. Which of the following combinations of quantum numbers (n, l, m l, m s ) do not represent permissible solutions of the Schrödinger equation for the electron in the hydrogen atom (i.e., which combination of quantum numbers is not allowed)? a. 6, 5, -5, 1/2 b. 9, 8, -4, 1/2 c. 6, -5, -1, 1/2 d. 8, 2, 2, 1/2 e. All are allowed. 12. Draw the molecular orbital diagram for B 2. The number of electrons in the 2pz molecular orbital is. a. 1 b. zero c. 3 d. 2 e Which of the following lists of atoms are arranged in order of INCREASING first ionization energy? a. Li < O < N < F b. F < O < N < Li c. Li < N < O < F d. Ca > Cs > S > Se e. Na < Sr < O < F 2

14. Which of the following lists of atoms are arranged in order of DECREASING atomic radius? a. Li > O > N > F b. Li > N > O > F c. F > O > N > Li d. Na > Sr > O > F e.

Which statement is true? a. Dextrorotary implies that light is rotated to the left. b. Racemic mixtures react with polarized light. c.

The hybridization associated with the central atom of a molecule in which all the bond angles are 180 is. a. sp 2 b. sp 3 d c. sp 3 d 2 d. sp e. sp 3 18.

3 14. Which of the following lists of atoms are arranged in order of DECREASING atomic radius? a. Li > O > N > F b. Li > N > O > F c. F > O > N > Li d. Na > Sr > O > F e. Ca < Cs < S < Se 15. Which of the following is a metalloid? a. carbon b. silicon c. hydrogen d. oxygen e. copper 16. Consider the following statements about optical isomers. Which statement is true? a. Dextrorotary implies that light is rotated to the left. b. Racemic mixtures react with polarized light. c. A solution with equal amounts of two optical isomers is called a racemic mixture. d. Optical isomers do not react with polarized light. e. All of these are true. 17. The hybridization associated with the central atom of a molecule in which all the bond angles are 180 is. a. sp 2 b. sp 3 d c. sp 3 d 2 d. sp e. sp The space-filling representation provided below is an example of a _ unit cell, which contains _ atom(s). a. simple cubic, 1 atom b. face centered cubic, 4 atoms c. body centered cubic, 2 atoms d. simple cubic, 8 atoms e. body centered cubic, 3 atoms 3

4 19. Which of the following materials is added to the blast furnace to produce slag? a. sulfur b. carbon c. silicon d. limestone e. none of these 20. Which ligand formula is incorrectly matched with its name as a ligand? Ligand / Name a. CO 2 3 / carbonato b. S 2 O 2 3 / sulfato c. SO 2 4 / sulfato d. F / fluoro e. O 2 / oxo 21. In any cubic lattice an atom lying at the corner of a unit cell is shared equally by how many unit cells? a. 1 b. 2 c. 4 d. 6 e The molecules in a sample of solid SO 2 are attracted to each other by a combination of a. H-bonding and ionic bonding b. London forces and dipole-dipole interactions c. covalent bonding and dipole-dipole interactions d. London forces and H-bonding e. none of these 23. Which model(s) accounts for the magnetism and color of coordination compounds? I. Lewis model II. localized electron model III. crystal field model a. I b. II c. I, II d. III e. none accounts for both phenomena 4

5 24. Consider an atom traveling at 1% of the speed of light. The de Broglie wavelength is found to be pm. Which element is this? a. H b. Ti c. P d. Mo e. C 25. Which of the following statements is (are) false? I. The layering in a hexagonal closest-packed structure is aba. II. A body-centered cubic unit cell has four atoms per unit cell. III. For unit cells having the same edge length, a simple cubic structure would have a smaller density than a body-centered cube. IV. Atoms in a solid consisting of only one element would have six nearest neighbors if the crystal structure were a simple cubic array. a. II b. II, III c. II, III, IV d. I, IV e. I 26. What is the denticity of the pictured ligand? ethylenediamine (en) a. 5 b. 2 c. 4 d. 1 e Which of the following molecules has three lone pairs of electrons on the central atom? a. XeF 2 b. XeF 4 c. SF 4 d. NCl 3 e. SF 6 5

6 28. Which of the following processes represents the ionization energy of bromine? a. Br(l) Br + (g) + e b. Br(s) Br + (s) + e c. Br(g) Br + (g) + e d. Br 2 (g) Br 2+ (g) + e e. Br(s) Br + (g) + e 29. Which of the following is the best explanation for how a water softener works? a. When hard water passes through the softener, the Ca 2+ and Mg 2+ ions are removed through electrolysis. b. The softener releases K + ions to counteract the Ca 2+ and Mg 2+ ions in the hard water. c. When hard water passes through the softener, the Ca 2+ and Mg 2+ ions precipitate out as Mg(OH) 2 and Ca(OH) 2. d. The softener releases an acid to interact with the Ca 2+ and Mg 2+ ions in the hard water to neutralize them. e. When hard water passes over a resin in the softener, the Ca 2+ and Mg 2+ ions in the water bind to the resin in place of Na + ions. 30. How many unpaired electrons are there in Ir(Br) 4 6? (Br is a weak-field ligand.) a. 3 b. 2 c. 0 d. 1 e Which one of the following is a covalent solid? a. sulfur trioxide b. sucrose, C 12 H 22 O 11 c. silicon carbide, SiC d. ammonium chloride e. nickel 32. The molecular geometry of PCl 3 is. a. tetrahedral b. octahedral c. pyramidal d. trigonal bipyramidal e. trigonal planar 33. Which of the following have 10 electrons in the d orbitals? a. Cu b. Mn c. Zn d. Fe e. two of the above 6

7 34. Which of the following is the correct order of boiling points for KNO 3, CH 3 OH, C 2 H 6, Ne? a. Ne < C 2 H 6 < CH 3 OH < KNO 3 b. Ne < C 2 H 6 < KNO 3 < CH 3 OH c. KNO 3 < CH 3 OH < C 2 H 6 < Ne d. Ne < CH 3 OH < C 2 H 6 < KNO 3 e. C 2 H 6 < Ne < CH 3 OH < KNO 3 Specify the number of unpaired electrons. 35. CuCl 2 (linear) a. 2 b. 4 c. 5 d. 0 e What is the wavelength of light that is emitted when an excited electron in the hydrogen atom falls from n = 5 to n = 2? a m b m c m d m e. none of these 37. Which response lists only the molecules given below that are paramagnetic? B 2, C 2, N 2, O 2, F 2 a. N 2 and F 2 b. B 2 and O 2 c. N 2 and O 2 d. B 2 and N 2 e. C 2, O 2, and F Which of the following species has square planar molecular geometry? a. CH 4 b. XeF 4 c. NH + 4 d. SO 2 4 e. SF Which one of the following properties of the alkali metals does not increase as the group is descended? a. first ionization energy b. atomic radius c. density d. ionic radius e. all of these increase 7

40. Which of these statements is false? a. The size of the unit cell of Li and Cs is the same. b. Metallic crystals are usually good electrical conductors. c. Molecular crystals usually have low melting points.

8 40. Which of these statements is false? a. The size of the unit cell of Li and Cs is the same. b. Metallic crystals are usually good electrical conductors. c. Molecular crystals usually have low melting points. d. Diamond is a covalent crystal. e. None of the statements is false. 41. Choose the species that is incorrectly matched with the electronic geometry about the central atom. Ion / Electronic Geometry a. BrO 4 / tetrahedral b. ClO 3 / tetrahedral c. NO 2 / trigonal planar d. ClO 4 / tetrahedral e. SO 2 3 / pyramidal 42. Which of the following pairs that refer to the metallurgy of iron / steel are incorrectly matched? a. zinc / added to steel to make it stainless steel b. CO / reducing agent in the metallurgy of iron c. pig iron / iron obtained from a blast furnace d. coke / form of carbon obtained from coal e. slag / calcium silicate by-product 43. What does the following figure represent? a. the overlap of two 1s orbitals to form a pi bond b. the overlap of two 2p orbitals to form a sigma bond c. the overlap of a 1s orbital and a 2p orbital to form a pi bond d. the overlap of a 1s orbital and a 2p orbital to form a sigma bond e. the overlap of two 2p orbitals to form a pi bond 44. What mass of CO 2 would be produced by heating a 300.-kg sample of limestone that is 52.0% CaCO 3? Assume complete reaction and no other source of carbon dioxide. a kg b. 132 kg c. 682 kg d kg e. 355 kg 8

9 45. Which of the following statements is true about p-type silicon? a. It does not conduct electricity as well as pure Si. b. It is produced by doping Si with P or As. c. Protons are the mobile charge carriers. d. All are true. e. None is true. 46. Which of the following has the highest melting temperature? a. CO 2 b. H 2 O c. P 4 d. S 8 e. MgF Which of the following statements is true? a. In the buildup of atoms, electrons occupy the 4f orbitals before the 6s orbitals. b. The exact location of an electron can be determined if we know its energy. c. Only three quantum numbers are needed to uniquely describe an electron. d. Ni has two unpaired electrons in its 3d orbitals. e. An electron in a 2s orbital can have the same n, l, and m l quantum numbers as an electron in a 3s orbital. 48. What is the formal charge on the nitrogen in NO 2 Cl? a. 0 b. +1 c. -1 d. +2 e Which one of the following molecules is nonpolar? a. NF 3 b. H 2 O c. CSO d. NH 3 e. CO Hydrogen bonds account for which of the following observation? a. Hydrogen is easily combustible with oxygen. b. Water molecules are bent or "V-shaped." c. Air is more dense than hydrogen gas. d. For its molar mass, water has a high boiling point. e. Hydrogen naturally exists as a diatomic molecule. 51. Choose the metal that reacts least vigorously with water. a. Sr b. Ca c. Ba d. Mg e. All of these react equally vigorously with water. 9

10 52. Which statement concerning alkali metals is incorrect? a. All of the free metals have melting points above 100 C. b. Alkali metals are not found free in nature because they are so easily oxidized. c. These metals are excellent electrical and thermal conductors. d. The free metals are very corrosive. e. The free metals, except lithium, are soft, silvery metals that can be cut with a knife. 53. Which of the following electron configurations is correct? a. Ca: [Ar]4s 1 3d 10 b. Bi: [Xe]6s 2 4f 14 5d 10 6p 3 c. Ga: [Kr]4s 2 3d 10 4p 1 d. Br: [Kr]4s 2 3d 10 4p 7 e. Mo: [Kr]5s 2 4d Consider the following orderings. I. Na + < Mg 2+ < Al 3+ < Si 4+ II. Be < Mg < Ca < Sr III. I < Br < Cl < F IV. Al < Si < P < Cl Which of these give(s) a correct trend in ionization energy? a. II, IV b. I, IV c. III d. I, III, IV e. none of them 55. The statement that "the lowest energy configuration for an atom is the one having the maximum number of unpaired electrons allowed by the Pauli principle in a particular set of degenerate orbitals" is known as a. Hund's rule b. the aufbau principle c. the Pauli exclusion principle d. Heisenberg uncertainty principle e. the quantum model 56. The first ionization energy of Mg is 735 kj/mol. The second ionization energy is a. More information is needed to answer this question. b. greater than 735 kj/mol c. 735 kj/mol d. less than 735 kj/mol e. None of these. 10

11 57. Which of the following will not form a coordination complex with a transition metal ion? a. NO b. CN c. NH 3 d. NO e. H 3 O Which one of the following pairs is incorrectly matched? Substance / Classification a. Fe / metallic solid b. diamond / molecular solid c. quartz / covalent solid d. CaF 2 / ionic solid e. sand / covalent solid 59. Which of the following crystal field diagrams is correct for Mn(CN) 3 6 (CN is a strong field ligand)? a. b. c. d. e. none of these 60. An element with the electron configuration [Xe] 6s 2 4f 14 5d 7 would belong to which class on the periodic table? a. transition elements b. alkaline earth elements c. halogens d. rare earth elements e. none of the above 11

12 ID: A Final Exam 2 Answer Section 1. A 2. D 3. D 4. D 5. D 6. D 7. C 8. A 9. D 10. A 11. C 12. A 13. A 14. B 15. B 16. C 17. D 18. A 19. D 20. B 21. E 22. B 23. D 24. D 25. A 26. B 27. A 28. C 29. E 30. A 31. C 32. C 33. E 34. A 35. D 36. B 37. B 1

13 ID: A 38. B 39. A 40. A 41. E 42. A 43. D 44. D 45. E 46. E 47. D 48. B 49. E 50. D 51. D 52. A 53. B 54. D 55. A 56. B 57. E 58. B 59. D 60. A 2

Chapter 9 practice questions

Class: Date: Chapter 9 practice questions Multiple Choice Identify the choice that best completes the statement or answers the question. 1. All of the following statements concerning valence bond (VB)