10.6 Practice Problems

Attempt these problems as if they were real exam questions in an exam environment.

Only look up information if you get severely stuck. Never look at the solution until you have exhausted all efforts to solve the problem.


  1. Nitrogen-15 radioactively decays into boron-11. What else is produced as a result of this decay?

    1. α particle
    2. β particle
    3. β+ particle
    4. positron

    Solution


  2. Phosphorus-30 radioactively decays into silicon-30. What else was produced as a result of this decay?

    1. positron
    2. α particle
    3. β particle
    4. electron

    Solution


  3. An isotope is found to be unstable due to the having too many neutrons. Which decay process will allow the isotope to reduce the number of neutrons it has?

    1. β decay
    2. β+ decay
    3. gamma ray emission
    4. combustion

    Solution


  4. An isotope is found to be unstable due to the having too many protons. Which decay process will allow the isotope to reduce the number of protons it has?

    1. electron capture
    2. beta decay
    3. gamma ray emission
    4. combustion

    Solution


  5. The iron-56 nuclide has a mass defect of 0.5302 amu. What is the binding energy (in MeV/nucleon) for this nuclide?

    1. 8.83
    2. 13.62
    3. 63.34
    4. 499.34

    Solution


  6. A 3.192 g sample of 95Tc is sealed in a container. Only 0.688 g remain after 44.2 h. What is the rate constant (in h–1)?

    1. –1.535
    2. 0.0347
    3. 0.143
    4. 3.431

    Solution


  7. A radioactive isotope is found to have a decay constant of 0.05 h–1. What is the half-life of this isotope (in days)?

    1. 0.0
    2. 0.578
    3. 13.86
    4. 332.64

    Solution


  8. A radioactive isotope is found to have a decay constant of 1.85 h–1. What is the half-life of this isotope (in h)?

    1. 0.375
    2. 1.048
    3. 6.337
    4. 12.893

    Solution


  9. The carbon-16 isotope has a mass defect of 0.11888 amu. What is the nuclear binding energy per nucleon (in MeV/nucleon to one decimal place) for this isotope?

    1. 2.4
    2. 4.8
    3. 6.9
    4. 9.3

    Solution