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9.1: Answer Key

  • Page ID
    25806
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    Electromagnetic Radiation

    1. a) gamma rays

    3. Gamma rays < X-rays < Ultraviolet < Visible Light < Infrared < Microwaves < Radio Waves

    The Quantum Mechanical Model

    5.

    clipboard_e9733f4ec2e048822356ef8ebc460d42b.png

     

     

    Electron Configurations

    7. a) Li: 1s22s1

    b) N: 1s22s22p3

    c) Cl: 1s22s22p63s23p5

    d) Ga: 1s22s22p63s23p64s23d104p1

     

    9. a) Xe: 1s22s22p63s23p64s23d104p65s24d105p6

    b) Ag: 1s22s22p63s23p64s23d104p65s24d9

    c) Cs: 1s22s22p63s23p64s23d104p65s24d105p66s1

    d) Hg: 1s22s22p63s23p64s23d104p65s24d105p66s24f145d10

    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] 5s24d3

    b) Se: [Ar] 4s23d104p4

    c) Ca: [Ar] 4s1

    d) Zn: [Ar] 4s23d10

     

    15. Write the noble gas electron configuration for the following elements.

    a) In: [Kr] 5s24d105p1

    b) Ba: [Xe] 6s2

    c) V: [Ar] 4s23d3

    d) Y: [Kr] 5s24d1

    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: _s1

    b) 5A: _s2_p3

    c) 6A: _s2_p4

     

    21. a) 8A: _s2_p6

    b) 2A: _s2

     

    23. a) Ra: [Rn] 7s2

    b) Pd: [Kr] 5s24d8

    c) Br: [Ar] 4s23d104p5

    d) Po: [Xe] 6s24f145d106p4

     

    25. a) At: [Xe] 6s24f145d106p5

    b) Pb: [Xe] 6s24f145d106p2

    c) Ba: [Xe] 6s2

    d) Ce: [Xe] 6s24f1

    27. a) Re: [Xe] 6s24f145d5

    b) Al: [Ne] 3s23p1

    c) Lr: [Rn] 7s25f14

    d) Os: [Xe] 6s24f145d6

    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) Mn2+: [Ar] 3d5

    b) Al3+: [He] 2s22p6 or         [Ne]

    c) I-: [Kr] 5s24d105p6             or         [Xe]

    d) Li+: [He]

    47. P3- ,S2- ,Cl- , K+ , Ca2+

     

     


    9.1: Answer Key is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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