Useful Constants and equations: K = o C + 273 Avogadro's number = 6.022 x 10 23 d = density = mass/volume R H = 2.178 x 10-18 J c = E = h = hc/ h = 6.626 x 10-34 J s c = 2.998 x 10 8 m/s E n = -R H Z 2 (1/n 2 ), Z = atomic number 2 1 1 E - R HZ 2 R = 0.08206 L atm / mol K n f n i 2 1 1A 1 H 1.008 3 Li 6.941 11 Na 22.99 19 K 39.10 37 Rb 85.47 55 Cs 132.9 87 Fr 223 2 2A 4 Be 9.012 12 Mg PERIODIC TABLE OF THE ELEMENTS 26 Fe 55.85 Atomic number Atomic mass 24.31 3 4 5 6 7 8 9 10 11 12 20 21 22 23 24 25 26 27 28 29 30 Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn 40.08 44.96 47.90 50.94 52.00 54.94 55.85 58.93 58.70 63.55 65.39 38 Sr 87.62 56 Ba 137.3 88 Ra 226 39 Y 88.91 57 La * 138.9 89 Ac 227 40 Zr 91.22 72 Hf 178.5 104 Rf 261 41 Nb 92.91 73 Ta 180.9 105 Db 262 42 Mo 95.94 74 W 183.9 106 Sg 266 43 Tc 98 75 Re 186.2 107 Bh 262 44 Ru 101.1 76 Os 190.2 108 Hs 265 45 Rh 102.9 77 Ir 192.2 109 Mt 266 46 Pd 106.4 78 Pt 195.1 110 Ds 271 47 Ag 107.9 79 Au 197.0 48 Cd 112.4 80 Hg 200.6 111 112 13 3A 5 B 10.81 13 Al 26.98 31 Ga 69.72 49 In 114.8 81 Tl 204.4 14 4A 6 C 12.01 14 Si 28.09 32 Ge 72.59 50 Sn 118.7 82 Pb 207.2 15 5A 7 N 14.01 15 P 30.97 33 As 74.92 51 Sb 121.8 83 Bi 209.0 16 6A 8 O 16.00 16 S 32.07 34 Se 78.96 52 Te 127.6 84 Po 209 17 7A 9 F 19.00 17 Cl 35.45 35 Br 79.90 53 I 126.9 85 At 210 18 8A 2 He 4.003 10 Ne 20.18 18 Ar 39.95 36 Kr 83.80 54 Xe 131.3 86 Rn 222 * Lanthanides Actinides 58 Ce 140.1 90 Th 232.0 59 Pr 140.9 91 Pa 231 60 Nd 144.2 92 U 238 61 Pm 145 93 Np 244 62 Sm 150.4 94 Pu 242 63 Eu 152.0 95 Am 243 64 Gd 157.3 96 Cm 247 65 Tb 158.9 97 Bk 247 66 Dy 162.5 98 Cf 251 67 Ho 164.9 99 Es 252 68 Er 167.3 100 Fm 257 69 Tm 168.9 101 Md 258 70 Yb 173.0 102 No 259 71 Lu 175.0 103 Lr 260
1. (3) A particular isotope of an element has a mass number of 152. There are 60 electrons in the +2 ion of the isotope. Identify the element, the number of protons and the number of neutrons of this particular isotope. a) 62 protons, 90 neutrons : Sm b) 66 protons, 86 neutrons : Dy c) 60 protons, 92 neutrons : Nd d) 63 protons, 89 neutrons : Eu e) 57 protons, 95 neurons : La 2. (4) A sample of water has a mass of 234.9 g at 24.0 o C. The density of water at 24.0 o C is 0.99707 g/ml. What is the volume of the water, in L and to the correct number of significant figures. a) 2.3559 x 10-1 b) 2.356 x 10-1 c) 2.36 x 10-1 d) 2.36 x 10 1 e) 2.356 x 10 1 3. (4) The atomic weight of Cu is 63.546. There are only two naturally occurring isotopes of copper, 63 Cu and 65 Cu. The natural abundance of the 63 Cu isotope must be approximately: a) 10% b) 30% c) 50% d) 70% e) 90% 4. (4) Which of the following compounds is named correctly? a) SnO 2 tin(ii) oxide b) NaNO 2 sodium nitrate c) NO nitrogen oxide d) Al 2 S 3 dialuminum trisulfide e) Na 2 O 2 sodium peroxide 5. (3) Which element is expected to be most chemically similar to phosphorus? a) S b) As c) Se d) Ge e) Si 6. (3) The element dysprosium, Dy, forms an oxide with the formula Dy 2 O 3. The corresponding bromide of dysprosium has the formula: a) Dy 2 Br 3 b) DyBr c) DyBr 2 d) DyBr 3 e) Dy 3 Br 2
7. (4) A fluoride salt of an alkaline earth metal has a molar mass of 78 g/mol. What is the formula of this salt? a) CaF 2 b) NaF 2 c) KF d) SrF 2 e) LiF 8. (4) A hydrogen atom with its electron in the n=3 energy level absorbs light with a wavelength of 1879 nm. The final energy level of the electron is? a) n = 1 b) n = 2 c) n = 4 d) n = 5 e) n = 6 9. (4) How many of the following elements have an incorrect electron configuration? Fe [Ar] 4s 2 3d 6 At [Xe] 6s 2 5d 10 6p 5 Os [Xe] 6s 2 5d 6 S [He] 3s 2 3p 4 Sr [Kr] 5s 2 a) one b) two c) three d) four e) five 10. (3) Which of the following has the largest number of unpaired electrons? a) Zn b) Bi c) Pd d) Te e) Rb 11. (3) Which of the following sets of quantum numbers is not possible? a) n = 1, l = 0, m l = 0 b) n = 3, l = 2, m l = -1 c) n = 4, l = 4, m l = 1 d) n = 2, l = 1, m l = -1 e) n = 6, l = 1, m l = -1 12. (4) Consider the following series of elements/ions: I. Al < Si < P < S II. Be < Mg < Ca < Sr III. I < Br < Cl < F IV. Na + < Mg 2+ < Al 3+ < Si 4+ Which gives the correct trend in size? a) I b) II c) III d) IV e) II and IV
13. (4) How many of the following sets represent an isoelectronic series? I. S +, Cl 2+, Ar, K - II. Ga 2-, As, Br 2+, Rb 4+ III. Li +, Na +, K +, Rb + IV CH 4, BH - + 4, NH 4 V. Mg 2-, Na -, Ne, F + a) 1 b) 2 c) 3 d) 4 e) 5 14. (3) Of the following, the atom with the largest first ionization energy is the one with the electron configuration: a) [Ne] 3s 2 3p 2 b) [Ne] 3s 2 3p 3 c) [He] 2s 2 2p 4 d) [He] 2s 2 2p 3 e) [Ar] 4s 2 3d 10 4p 3 15. (3) Which of the following elements has the largest second ionization energy? a) Mg b) Al c) Na d) Li e) Ca Shown below are four energy diagrams. Use these to answer the next two questions. 16. (3) Which of these energy diagrams describes the ground state of copper, Cu? a) b) c) d) e) none of them (a-d) 17. (3) Which of these energy diagrams describes an excited state of copper, Cu? a) b) c) d) e) none of them (a-d)
Shown below are five covalent compounds. Use them to answer the next two (2) questions: SCl 2 SiCl 4 PCl 5 Cl 2 NCl 3 18. (3) In which compound are the bonds most polar? a) SCl 2 b) SiCl 4 c) PCl 5 d) Cl 2 e) NCl 3 19. (3) How many of these compounds are polar? a) 1 b) 2 c) 3 d) 4 e) 5 Draw the Lewis structures for the following compounds and use this information to answer the next four questions. I. SeO 2 II. XeCl 4 III. HCN IV. CO 3 2-20. (3) How many of these compounds exhibit resonance? a) 0 b) 1 c) 2 d) 3 e) 4 21. (3) How many of these compounds are polar? a) 0 b) 1 c) 2 d) 3 e) 4 22. (3) How many of these compounds have a central atom with sp 2 hybridization? a) 0 b) 1 c) 2 d) 3 e) 4 23. (3) What is the largest (most positive) formal charge in CO 2-3? a) +2 b) +1 c) 0 d) -1 e) -2
Shown to the right is the incomplete structure of the artificial sweetener, Aspartame. Complete the structure and use it to answer the next three (3) questions. 24. (3) How many bonds are present in this structure? a) 2 b) 3 c) 4 d) 5 e) 6 25. (3) What are the approximate bond angles around the starred atoms in this compound? C N O a) 120 109.5 180 b) 109.5 109.5 109.5 c) 120 109.5 109.5 d) 109.5 120 120 e) 120 120 180 26. (3) The energy diagram below corresponds to which of the starred atoms? a) C * b) O * c) N * d) more than one of them e) none of them
Draw the Lewis structures for the following compounds and use this information to answer the next four questions. I. IF 3 II. SeCl 4 III. SO 3 IV. ClF 5 27. (3) Which of these compounds obeys the octet rule? a) I b) II c) III d) IV e) more than one of them (I - IV) 28. (3) Which of these compounds has a central atom with d 2 sp 3 hybridization? a) I b) II c) III d) IV e) more than one of them (I - IV) 29. (3) Which of these compounds has a formal charge of +2 on the central atom? a) I b) II c) III d) IV e) more than one of them (I - IV) 30. (3) How many of these compounds are matched to their correct molecular shape? IF 3 SeCl 4 SO 3 ClF 5 T shaped square planar trigonal planar square pyramidal a) 0 b) 1 c) 2 d) 3 e) 4 Shown below is the Lewis structure of a compound with an unknown central atom, X. Use this structure to answer the next two questions. 31. (3) Which of the atoms listed below could be X? F F X S F 3- a) C b) O c) Cl d) Se e) more than one of these (a-d) could be X 32. (3) This ion is: a) square planar and polar b) square planar and non-polar c) see saw shaped and polar d) see saw shaped and non-polar e) none of the above (a-d)