Chapter 8 Atomic Electronic Configurations and Periodicity

Chapter 8 Electron Configurations Page 1 Chapter 8 Atomic Electronic Configurations and Periodicity 8-1. Substances that are weakly attracted to a magnetic field but lose their magnetism when removed from the magnetic field are called. (a) ferromagnetic (b) diamagnetic (c) paramagnetic (d) antiferromagnetic 8-2. Substances that retain their magnetism when withdrawn from a magnetic field are called. (a) ferromagnetic (b) diamagnetic (c) paramagnetic (d) antiferromagnetic 8-3. Electron spin is quantized in such a way that, in an external magnetic field, (give number) of orientations of the electron spin are possible. (a) one (b) two (c) three (d) the number is not definite 8-4. What is the maximum number of electrons that can be placed in a single 5f orbital? (a) two (b) eight (c) fourteen (d) eighteen 8-5. Which of the following elements is a p-block element? (a) copper (b) chlorine (c) chromium (d) sodium 8-6. Which of the following elements is a d-block element? (a) copper (b) chlorine (c) aluminum (d) sodium 8-7. What element has the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 4? (a) O (b) S (c) Se (d) Si

Chapter 8 Electron Configurations Page 2 8-8. What element has the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 1? (a) Na (b) B (c) K (d) Al 8-9. What element has the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 6 3d 3 4s 2? (a) Ca (b) Mn (c) V (d) Cl 8-10. What element has the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2? (a) Zn (b) Ge (c) Ca (d) Ni 8-11. What element has the electron configuration 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 3? (a) Ga (b) P (c) V (d) As 8-12. Which rare gas symbol would be used for the rare gas notation for the electronic configuration of the element silver? (a) argon (b) krypton (c) xenon (d) radon 8-13. Which rare gas symbol would be used for the rare gas notation for the electronic configuration of the element platinum? (a) argon (b) krypton (c) xenon (d) radon 8-14. What element has the electron configuration [Kr] 4d 5 5s 1? (a) W (b) Ru (c) Mo (d) Pm 8-15. What element has the electron configuration [Rn] 5f 3 6d 1 7s 2? (a) U (b) Nd (c) Ta (d) Bi

Chapter 8 Electron Configurations Page 3 8-16. What element has the electron configuration [Xe] 4f 14 5d 10 6s 2 6p 2? (a) Hf (b) Pb (c) Lu (d) Sn 8-17. What element has the following electron configuration? 1s 2s 2p 3s 3p (a) Cl (b) Be (c) S (d) Ti 8-18. What element has the following electron configuration? [Ar] five 3d orbitals 4s 4p (a) Sc (b) Ca (c) Al (d) Mo 8-19. The electron configuration for B in the orbital box notation is 1s 2s 2p Give a set of quantum numbers for the last electron in this element. n = l = m l = m s = 8-20. What is the electronic configuration of P 3-? (a) [Ne] 3s 2 3p 6 (b) [Ne] 3s 2 (c) [Ne] 3s 2 3p 3 (d) [Ne] 3p 6

Chapter 8 Electron Configurations Page 4 8-21. What is the electronic configuration of Br -? (a) [Ar] 4s 2 4p 5 (b) [Ar] 4s 2 4p 6 (c) [Kr] 4s 2 4p 6 (d) [Kr] 8-22. What is the electronic configuration of Se 2-? (a) [Ar] 4s 2 4p 6 (b) [Ar] 4s 2 4p 8 (c) [Ar] 4s 2 4p 6 3d 10 (d) [Ar] 8-23. Which of the following is the correct electronic configuration for the iron(iii) ion? (a) [Ar] 3d 5 (b) [Ar] 4s 2 3d 3 (c) [Kr] 4s 2 3d 3 (d) [Kr] 3d 5 8-24. Which of the following is the correct electronic configuration for the zirconium(ii) ion? (a) [Ar] 4d 2 (b) [Ar] 5s 2 (c) [Kr] 5s 2 (d) [Kr] 4d 2 8-25. Which of the following is the correct electronic configuration for the nickel(ii) ion? (a) [Ar] 3d 8 (b) [Ar] 4s 2 3d 6 (c) [Kr] 4s 2 3d 6 (d) [Kr] 3d 8 8-26. Which of the following is the correct electronic configuration for the molybdenum(iii) ion? (a) [Ar] 4d 3 (b) [Ar] 5s 2 4d 1 (c) [Kr] 5s 2 4d 1 (d) [Kr] 4d 3 8-27. Which of the following is the correct electronic configuration for the cadmium(ii) ion? (a) [Kr] 4d 8 (b) [Kr] 4d 10 (c) [Kr] 5s 2 4d 8 (d) [Kr] 5s 1 4d 9 8-28. Which of the following is the correct electronic configuration for the tin(ii) ion? (a) [Kr] 5s 2 5p 2 4d 10 (b) [Kr] 5s 2 5p 2 4d 8 (c) [Kr] 5s 2 4d 10 (d) [Kr] 5p 2 4d 10

Chapter 8 Electron Configurations Page 5 8-29. The electronic configuration [Ar] 3d 6 is typical of which of the following? (a) chromium (b) iron(ii) (c) rhodium(iii) (d) molybdenum 8-30. What ion corresponds to the following electron configuration? [Ar] five 3d orbitals (a) Fe 3+ (b) Co 3+ (c) Rh 3+ (d) Ni 2+ 4s 8-31. Which of the following ions is diamagnetic? (a) Ti 2+ (b) Mg 2+ (c) V 2+ (d) Cr 2+ 8-32. Which of the following ions is paramagnetic? (a) Ca 2+ (b) Zn 2+ (c) Sc 3+ (d) Zr 2+ 8-33. Which of the following elements has two unpaired electrons when it is a +3 ion? (a) vanadium (b) aluminum (c) cadmium (d) antimony 8-34. Which of the following elements has three unpaired electrons when it is a +2 ion? (a) zinc (b) strontium (c) zirconium (d) cobalt 8-35. Which of the following best describes the variation of atomic radii of the elements with respect to their position on the periodic table? (a) increases across a period, increases down a group. (b) increases across a period, decreases down a group. (c) decreases across a period, increases down a group. (d) decreases across a period, decreases down a group.

Chapter 8 Electron Configurations Page 6 8-36. The energy needed to remove an electron from an atom in the gas phase is called (a) electron affinity (b) atomic radius (c) electronic configuration (d) ionization energy 8-37. Which of the following best describes the variation of ionization energy of the elements with respect to their position on the periodic table? (a) increases across a period, increases down a group. (b) increases across a period, decreases down a group. (c) decreases across a period, decreases down a group. (d) decreases across a period, increases down a group. 8-38. Which of the following best describes the order of increasingly positive electron affinity of the elements with respect to their position on the periodic table? (a) more positive across a period, more positive down a group. (b) more positive across a period, less positive down a group. (c) less positive across a period, less positive down a group. (d) less positive across a period, more positive down a group. 8-39. Which type of element below has atomic sizes that remain almost identical across a period? (a) main group metals (b) main group nonmetals (c) transition metal elements (d) none of these 8-40. Which of the following groups of elements is arranged correctly in order of increasing first ionization energy? (a) B < O < Al < F (b) Al < B < O < F (c) B < O < F < Al (d) F < O < B < Al 8-41. Which of the following groups of elements is arranged correctly in order of increasing first ionization energy? (a) Mg < C < N < F (b) N < Mg < C < F (c) Mg < N < C < F (d) F < C < Mg < N 8-42. Which of the following groups of elements is arranged correctly in order of increasing affinity for electrons (that is, electron affinity becomes more positive)? (a) Mg < S < Al < Cl (b) Al < Mg < S < Cl (c) Mg < Al < S < Cl (d) Cl < S < Mg < Al

Chapter 8 Electron Configurations Page 7 8-43. Which of the following groups of elements is arranged correctly in order of decreasing atomic radius? (a) Mg > S > Al > Cl (b) Al > Mg > S > Cl (c) Mg > Al > S > Cl (d) Cl > S > Mg > Al 8-44. Which of the following groups of elements is arranged correctly in order of decreasing atomic radius? (a) B > O > Al > F (b) Al > B > O > F (c) B > O > F > Al (d) F > O > B > Al 8-45. Which of the following elements would have the greatest difference between the first and the second ionization energy? (a) lithium (b) carbon (c) fluorine (d) nitrogen 8-46. Which of the following elements would have the greatest difference between the first and the second ionization energy? (a) calcium (b) arsenic (c) bromine (d) potassium 8-47. Which of the following is expected to have the largest radius? (a) P 3- (b) S 2- (c) Cl - (d) Ar 8-48. Which of the following is expected to have the smallest radius? (a) S 2- (b) K + (c) Cl - (d) Ca 2+ 8-49. What is the group number of the main group elements of the periodic table that are expected to form +2 ions? (a) group 1A (b) group 2A (c) group 3A (d) group 4A

Chapter 8 Electron Configurations Page 8 8-50. Which of the following elements has the most metallic character? (a) calcium (b) lithium (c) cesium (d) potassium 8-51. Which of the following elements has the least metallic character? (a) hydrogen (b) iodine (c) sulfur (d) fluorine 8-52. An element having which of the following electronic configurations would have the greatest ionization energy? (a) [He] 2s 2 2p 3 (b) [He] 2s 2 2p 5 (c) [Ne] 3s 2 3p 3 (d) [Ne] 3s 2 3p 5 8-53. An element having which of the following electronic configurations would have the largest atomic radius? (a) [He] 2s 2 2p 3 (b) [He] 2s 2 2p 5 (c) [Ne] 3s 2 3p 3 (d) [Ne] 3s 2 3p 5 8-54. An element having which of the following electronic configurations would have the smallest ionization energy? (a) [He] 2s 2 (b) [He] 2s 2 2p 1 (c) [Ne] 3s 2 (d) [Ne] 3s 2 3p 1 8-55. Which of the following ions is least likely to be formed? (a) Be 2+ (b) S 2- (c) Al 3+ (d) Na 2+ 8-56. Which of the following ions is most likely to be formed? (a) Mg 3+ (b) Na + (c) Al 4+ (d) N 3-

Chapter 8 Electron Configurations Page 9 8-57. Which of the following groups of isoelectronic ions is arranged correctly in order of increasing size? (a) Na + < O 2- < F - (b) F - < Na + < O 2- (c) Na + < F - < O 2- (d) F - < O 2- < Na + 8-58. The maximum number of electrons that may be associated with the set of quantum numbers n = 5 and l = 3 is. (a) 2 (b) 6 (c) 10 (d) 14 8-59. Tell how many electrons can be associated with each of the following sets of quantum numbers: Quantum Numbers Maximum Number of Electrons n = 3, l = 2, m = -2 l n = 4 l = 4, m = -2, m = +1/2 l s n = 5 l = 2 n = 4 8-60. Which of the following is NOT an allowed set of quantum numbers: n l m l m s (a) 4 1-1 -1/2 (b) 3 1 0 +1/2 (c) 2 1-2 +1/2 (d) 5 4-4 -1/2 8-61. Compare the elements Na, B, Al, and C with regard to the following properties: (i) Which has the largest atomic radius? (ii) Which has the most positive electron affinity? (iii) Which has the largest ionization energy?

Chapter 8 Electron Configurations Page 10 8-62. Periodic trends (i) Which of the elements Ca, Ti, and As has the largest atomic radius? (ii) Which should be larger, the oxide ion, O 2-, or the oxygen atom, O? (iii) (iv) Of the three elements C, Si, and P, which should be the largest? Which of these three elements C, Si, and P should have the largest first ionization energy? 8-63. Compare the properties of two elements labeled A and B. A = [Ar] 3d 10 4s 2 B = [Kr] 5s 2 4d 10 5p 5 (i) Is element A a nonmetal or a metal? (ii) Which element should have the greater electron affinity? (iii) Which element should have the larger first ionization energy? 8-64. Periodic properties. (i) Of the elements Al, N, O, and P, which has the largest atomic radius? (ii) Of the elements Al, N, O, and P, which has the most positive electron affinity? (iii) Of the elements Al, N, O, and P, which has the largest first ionization energy? (iv) Which is larger, Cl or Cl -? 8-65. Periodic properties. (i) Which should have the largest difference between the first and second ionization energy: Si, Na, P, or Mg? (ii) Which has the largest ionization energy: O, S, or Se? (iii) What element in Group 7A has the most positive electron affinity? (iv) What element in the 4th period has the most positive electron affinity? (v) What element in the 4th period has the largest radius?

Chapter 8 Electron Configurations Page 11 ANSWERS CHAPTER 8 1. c 11. d 21. d 2. a 12. b 22. c 3. b 13. c 23. a 4. a 14. c 24. d 5. b 15. a 25. a 6. a 16. b 26. d 7. b 17. c 27. b 8. d 18. a 28. c 9. c 19. 2, 1, +1, + 1/2 29. b 10. a 20. a 30. b 31. b 41. a 51. d 32. d 42. c 52. b 33. a 43. c 53. c 34. d 44. b 54. c 35. c 45. a 55. d 36. d 46. d 56. b 37. b 47. a 57. c 38. b 48. d 58. d 39. c 49. b 59. 2, 1, 10, 32 40. b 50. c 60. c 61. Na, C, C 62. (i) = Ca; (ii) = O 2- ; (iii) = Si; (iv) = C 63. (i) = A; (ii) = B; (iii) = B 64. (i) = A; (ii) = O; (iii) = N; (iv) = Cl - 65. (i) = Na; (ii) = O; (iii) = Cl; (iv) = Br; (v) = K