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          tiL12214_appe_643-698.indd Page 664  09/10/10  8:37 AM user-f463
          tiL12214_appe_643-698.indd Page 664  09/10/10  8:37 AM user-f463              Volume/207/MHDQ243/tiL12214_disk1of1/0073512214/tiL12214_pagefile






                                                                                                    –20
                                                                           8.4.   For n = 6, E H  = –6.05 × 10  J
                    CHAPTER 8
                                                                                                    –19
                                                                                 For  n = 2, E L  = –5.44 × 10  J
                                    –27
                    8.1.    m = 1.68 × 10  kg                                                 –34
                                                                                    h = 6.63 × 10  J·s
                                    3
                           v = 3.22 × 10  m/s
                                                                                     f = ?
                                    –34
                           h = 6.63 × 10  J·s
                                                                                                    E H  – E L

                                                                                    hf = E H  – E L   ∴  f =   _

                          λ = ?                                                                       h
                                                                                                                         –19
                                         h _                                                        (–6.05 × 10  J) – (–5.44 × 10 J)
                                                                                                            –20

                                     λ =                                                            ___

                                         mv                                                      f =
                                                                                                                 –34
                                                                                                          6.63 × 10  J·s
                                                     –34
                                               6.63 × 10  J·s
                                         ___
                                                                                                          –19
                                                                                                             J
                                       =                                                            4.84 × 10 _
                                                                                                    __



                                                            3 m _



                                                –27

                                         (1.68 × 10  kg) ( 3.22 × 10          )                   =       –34 J·s
                                                             s                                      6.63 × 10
                                                    –34
                                                             J·s
                                         ____                                                             14 1 _
                                              6.63 × 10
                                       =                                                          = 7.29 × 10

                                                               m _
                                                                                                            s
                                                –27
                                                         3
                                         (1.68 × 10 )(3.22 × 10 ) kg ×

                                                                s                                          14
                                                                                                  =  7.29 × 10  Hz
                                                  kg·m
                                                  _  2
                                                       × s
                                               –34


                                         6.63 × 10 _                                                    E 1 _
                                         __
                                                   s·s





                                       =              m _                  8.5.   (n = 1) = –13.6 eV   E n  =
                                         5.41 × 10 –24  kg ×                                            n 2

                                                       s                           E = ?
                                                                                                        _


                                                 kg·m·m
                                               –10 _ _ _                                              =   –13.6 eV
                                                              s
                                                         1

                                       = 1.23 × 10                                                        1 2
                                                       ×        ×
                                                    s    kg  m
                                                                                                      = –13.6 eV
                                                –10
                                       =  1.23 × 10  m
                                                                                 Since the energy of the electron is –13.6 eV, it will require
                    8.2.   (a)   n = 6         E L _                                            –18
                                           E n  =                                13.6 eV (or 2.17 × 10  J) to remove the electron.

                            E L  = –13.6 eV    n 2
                                                                                              11
                                                                           8.6.   q/m = –1.76 × 10  C/kg   __
                                                                                                             charge
                                               –13.6 eV
                            E 6  = ?           _                                                      mass =


                                           E 6  =                                             –19          charge/mass
                                                 6 2                               q = –1.60 × 10  C
                                                                                                                   –19
                                                                                                           –1.60 × 10  C

                                               _                                   m = ?                 =   __
                                               –13.6 eV



                                             =                                                                     11 C _
                                                  36                                                       –1.76 × 10

                                                                                                                    kg
                                             =  –0.378 eV
                                                                                                                   –19
                                                                                                           __            kg
                                                                                                                         _
                                                                                                           –1.60 × 10

                                                         J
                                                      –19 _                                              =                 C ×
                          (b)        = (–0.378 eV)( 1.60 × 10          )                                   –1.76 × 10 –11  C

                                                        eV                                                        –31
                                                           J
                                                          _
                                                    –19

                                     = (–0.378)(1.60 × 10 ) eV ×                                         =  9.09 × 10  kg
                                                           eV              8.7.   λ = 1.67 × 10  m
                                                                                           –10
                                               –20
                                     =  –6.05 × 10  J                            m = 9.11 × 10  kg
                                                                                            –31
                    8.3.   (a)   Energy is related to the frequency and Planck’s constant in   v = ?
                             equation 8.1, E = hf. From equation 8.4,                      h _       h _


                                                                                       λ =          ∴  v =
                                                                                                    mλ
                                                                                          mv
                            hf  = E H  – E L   ∴  E = E H  – E L
                                                                                                                 –34
                                                                                                          6.63 × 10  J·s
                                            –20
                          For  n = 6, E H  = 6.05 × 10  J                                        v =   ___







                                                                                                                       –10
                                                                                                            –31
                                            –19
                          For  n = 2, E L  = 5.44 × 10  J                                           (9.11 × 10  kg) (1.67 × 10  m)
                                                                                                                –34
                                                                                                    ___ _
                                                                                                                         J·s
                                                                                                          6.63 × 10
                             E = ? J                                                              =


                                                                                                                     –10
                                                                                                            –31
                                                                                                    (9.11 × 10 ) (1.67 × 10 ) kg·m
                                         E = E H  – E L                                                          2
                                                                                                             kg·m
                                                                                                             _
                                                                 –19
                                                     –20

                                           = (–6.05 × 10  J) – (–5.44 × 10  J)                      ___


                                                                                                                  × s

                                                                                                           –34
                                                                                                               s·s
                                                                                                    6.63 × 10




                                                    –19
                                           =  4.84 × 10  J                                        =        –40
                                                                                                    1.52 × 10  kg·m
                          (b)  E H  = –0.377 eV*                                                           6 _ _ _
                                                                                                            kg·m·m
                                                                                                                        1
                                                                                                                    1

                                                                                                  = 4.36 × 10
                                                                                                                  ×        ×
                              E L  = –3.40 eV*                                                                s     kg  m
                              E = ? eV                                                                     6 m _
                                                                                                  =  4.36 × 10

                                                                                                             s
                                         E = E H  – E L
                                                                                             2
                                                                                           2
                                           = (–0.377 eV) – (–3.40 eV)      8.8.   (a)  Boron: 1s 2s 2p 1
                                                                                                  6
                                                                                                    2
                                                                                                2
                                                                                              2
                                                                                 (b) Aluminum: 1s 2s 2p 3s 3p 1
                                           =  3.02 eV                                        2  2  6  2  6  1
                                                                                 (c) Potassium: 1s 2s 2p 3s 3p 4s
                                               *From Figure 8.11.
                                                                           8.9.   (a)  Boron is atomic number 5 and there are 5 electrons.
                                                                                 (b)   Aluminum is atomic number 13 and there are 13 electrons.
                                                                                 (c)   Potassium is atomic number 19 and there are 19 electrons.
                   664     APPENDIX E  Solutions for Group A Parallel Exercises                                         E-22
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