SCI 270: On Nuclear Technology Practice Problems  

11. Ionizing Radiation and Safety

You are not required to hand in answers for this assignment, but in your search for answers for these questions, you may learn something that is benefitial.
  1. At 273 K and 1 atm pressure, 1.0 mol of N2 occupies 22.4 L. Calculate the number of N2 molecules in 1.0 L. At 277 K, 1.0 L of water weighs 1.0 kg. Calculate the number of moles of water in 1.0 L. Calculate the number of H2O molecules in 1.0 L at 277 K. The density of lead (Z, 82; at. wt. 207.2) is 11.29 g/mL, calculate the number of lead atoms in 1.0 L. (1.0 mole of N2 has 6.02x1023 N2 molecules).

    The purpose is to compare the particle density of solid, liquid, and gaseous states of some material so that you can picture or estimate the number of collisions an ionizing particle has over its path.

  2. Explain the process by which beta particles lose energy when they pass by a nucleus. What radiation is produced in this process?

  3. Describe the mechanisms by which gamma-rays interact with matter. Explain each mechanism separately.

  4. What is the quality factor or rbe? A person weighing 100 kg received 1 Gy of fast neutron radiation dose. How much radiation in unit Sv is exposed to?

  5. Calculate the dose (in rem and Sv) received on the first day by a patient weighing 50 kg who has been injected with 1.0 microcurie of 131I, half-life 8 days. Consider the energy released per disintegration being 2 MeV, all absorbed by the tissues of the patient.
Answers to Practice Problems 11 are available, but do your part first. Your skills are tested and they are yours forever.

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