SCI 270: On Nuclear Technology Practice Problems  
Answers are given for your reference only. Please do your part of the learning, because no one else will be able to do that for you.

Your skills of problem solving are tested and useful in the future. Answers are useless. Acquiring skills and abilities are the goals of learning, marks indications of your performances on these tasks.

7. Radioactive and Stable Nuclides

  1. What are the number-of-neutrons to number-of-protons ratio for the stable nuclides:

    1H_1_ 14N___ 35Cl___ 56Fe___ 80Br___ 100Rh___ 150Sm___ 200Hg___ 209Bi___

    _0.0___

    _1.0___

    _1.1___

    _1.2___

    _1.3___

    _1.2___

    _1.4___

    _1.5___

    _1.52__
    The purpose is to work out the ratios yourself so that you realize how the numbers of protons and the numbers of neutrons in stable nuclides vary. This is an important factor contributing to the stability of nuclides.

     

     

  2. Magic numbers contribute to the stability of nuclides. From a source other than SCI270 lecture notes, find the stable isotopes for the following:

    Source:
    ________
    4He2
    __3He________________
    6Li3 7Li3
    16O8
    __17O, 18 _____________________________
    14N7The only one
    40Ca20
    42Ca, 43Ca, 44Ca, 46Ca, 48Ca, _
    45Sc21The only one
    54Fe2656Fe, 57Fe, 58Fe 59Co27The only one
    58Ni28
    60Ni, 61Ni, 62Ni, 64Ni _
    63Cu2965Cu29
    112Sn50
    _114Sn, 115Sn, 116Sn, 117Sn, 118Sn, 119Sn, 120Sn, 122Sn, 124Sn, _
    121Sb51123Sb51
    204Pb82
    _206Pb, 207Pb, 208Pb _
    209Bi83Number of neutron = _126_
    The only one

    Double magic number nuclides: _ 4He2, 16O8, 40Ca20, 48Ca20, 208Pb82 _
    For your information, 209Bi (Z = 83) is stabe, whereas 209Pb (Z = 82) is a beta emitter.

     

     

  3. Provide the (missing) masses in amu, calculate binding energies (BE) in MeV, average binding energies in MeV, and the mass excess in MeV of the following nuclides. Masses of hydrogen and neutron are 1.007825 and 1.008665 amu respectively.
    Nuclide2D 4He 14C 14N 16O 56Fe 59Co 238U
    Mass
    _2.0140
    4.00260
    14.003241
    14.003074 15.994915 55.9349 58.9332 238.0508
    Binding
    energy

    _2.224_

    28.295

    105.284

    104.658

    127.619

    492.253

    517.308

    1801.694
    Average
    BE

    1.112

    7.074

    7.520

    7.476

    7.976

    8.790

    8.768

    7.570
    Mass
    excess

    13.135

    2.424

    3.019

    2.863

    4.736

    -60.60

    -62.223

    47.32

     

     

  4. The disintegration energies for isobars with mass number 133 are given below. Make a plot of energy content as a function of Z for these isobars from the disintegration energy (in MeV). Te (Z=52), 2.4; I (Z=53), 1.8; Xe (Z=54), 0.43; Cs (Z=55), stable; Ba (Z=56), 0.489; La (Z=57), 1.2l Ce(Z=58), 1.8.

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