Electromagnetic Radiation 1. a) gamma rays 3. Gamma rays < X-rays < Ultraviolet < Visible Light < Infrared < Microwaves < Radio Waves The Quantum Mechanical Model 5. Electron Configurations 7. a) Li: 1s 2 2s 1 b) N: 1s 2 2s 2 2p 3 c) Cl: 1s 2 2s 2 2p 6 3s 2 3p 5 d) Ga: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 1 9. a) Xe: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 b) Ag: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 9 c) Cs: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 1 d) Hg: 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 11. a) P: 1s 2s 2p 3s 3p ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑ ↑ ↑ 3 unpaired electrons b) K: 1s 2s 2p 3s 3p 4s ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑_ 1 unpaired electron c) He: 1s ↑↓ No unpaired electrons d) Al: 1s 2s 2p 3s 3p ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑↓ ↑ 1 unpaired electron 13. a) Nb: [Kr] 5s 2 4d 3 b) Se: [Ar] 4s 2 3d 10 4p 4 c) Ca: [Ar] 4s 1 d) Zn: [Ar] 4s 2 3d 10 15. Write the noble gas electron configuration for the following elements. a) In: [Kr] 5s 2 4d 10 5p 1 b) Ba: [Xe] 6s 2 c) V: [Ar] 4s 2 3d 3 d) Y: [Kr] 5s 2 4d 1 Valence Electrons 17. a) Cd: 5s ↑↓ No unpaired electrons b) Na: 3s ↑_ 1 unpaired electron c) I: 5s 5p ↑↓ ↑↓ ↑↓ ↑_ 1 unpaired electron d) Sn: 5s 5p ↑↓ ↑ ↑ __ 2 unpaired electrons Electron Configurations and the Period Table 19. a) 1A: _s 1 b) 5A: _s 2 _p 3 c) 6A: _s 2 _p 4 21. a) 8A: _s 2 _p 6 b) 2A: _s 2 23. a) Ra: [Rn] 7s 2 b) Pd: [Kr] 5s 2 4d 8 c) Br: [Ar] 4s 2 3d 10 4p 5 d) Po: [Xe] 6s 2 4f 14 5d 10 6p 4 25. a) At: [Xe] 6s 2 4f 14 5d 10 6p 5 b) Pb: [Xe] 6s 2 4f 14 5d 10 6p 2 c) Ba: [Xe] 6s 2 d) Ce: [Xe] 6s 2 4f 1 27. a) Re: [Xe] 6s 2 4f 14 5d 5 b) Al: [Ne] 3s 2 3p 1 c) Lr: [Rn] 7s 2 5f 14 d) Os: [Xe] 6s 2 4f 14 5d 6 29. a) Mg: 2 b) K: 2 c) Na: 1 d) Li: Lithium does not have a 3s orbital shell, therefore there are zero 3s electrons 31. a) Te b) Sr c) Nb d) In 33. a) As b) Ge c) Cu d) K 35. a) No b) C c) Kr d) W Periodic Trends 37. a) Rb b) Te c) Ge d) Pb 39. a) Y b) K c) Tc d) Cs 41. O < Kr < Be < Sr < K Cumulative Challenge Problems 43. a) n=1, 2 b) n=2, 8 c) n=3, 18 d) n=4, 32 45. a) Mn 2 + : [Ar] 3d 5 b) Al 3 + : [He] 2s 2 2p 6 or [Ne] c) I - : [Kr] 5s 2 4d 10 5p 6 or [Xe] d) Li + : [He] 47. P 3- ,S 2- ,Cl - , K + , Ca 2 +