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4.2.4: Practice Isotopes

  • Page ID
    235931
  • Exercise \(\PageIndex{1}\)

    For each isotope shown, give the number of protons, neutrons, and electrons.  These isotopes are neutral (charge = 0).

    a)   115B

    b)  4119K

    c)  7032Ge

    Answer a

    5 protons, 6 neutrons, 5 electrons

    Answer b

    19 protons, 22 neutrons, 19 electrons

    Answer c

    32 protons, 38 neutrons, 32 electrons

     

    Exercise \(\PageIndex{1}\)

    For each isotope shown, give the number of protons, neutrons, and electrons. 

    d)   4420Ca2+

    e)  4119K1+

    f)  188O2–

    Answer d

    20 protons, 24 neutrons, 18 electrons

    Answer e

    19 protons, 22 neutrons, 18 electrons

    Answer f

    8 protons, 10 neutrons, 10 electrons

     

     

    Exercise \(\PageIndex{1}\)

    Given the number of protons, neutrons, and electrons, what would be the mass number and the charge number of each isotope?  What would be the atomic number?  The identity of the element? 

    g)  7 protons, 7 neutrons, 10 electrons

    h)  15 protons, 16 neutrons, 15 electrons

    i)  25 protons, 30 neutrons, 23 electrons

    Answer g

    Mass number is 14, charge is –3.  Atomic number is 7, identity is nitrogen (N).

    Answer h

    Mass number is 31, charge is 0.  Atomic number is 15, identity is phosphorus (p).

    Answer i

    Mass number is 55, charge is +2.  Atomic number is 25, identity is manganese (Mn).

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