Half Lives

• What is the nature of radioactive decay?

  It is random.
• Can the decay of a single atom be predicted?

  No, it cannot be predicted.
• What can be predicted about the decay patterns of large numbers of atoms?

  They can be predicted.
• What is the definition of half-life?

  Time for half of a sample to decay.
• What does half-life indicate about a radioactive isotope?

  It indicates the time for half to decay.
• How can half-life values be used in calculations?

  To calculate remaining radiation over time.
• What is the relationship between half-life and the amount of radiation present over time?

  • Half-life determines the decay rate.
  • After each half-life, half of the sample remains.
  • Useful for calculating radiation levels over time.
• What is the count rate in counts per minute for a radioactive sample?

  It varies based on the sample's half-life.
• How should half-life values be used in radiation calculations?

  To calculate radiation present after time periods.
• How can you use half-life to calculate radiation after different time periods?

  By applying the half-life repeatedly.
• What factors influence the amount of radiation present after a given time?

  • The half-life of the radioactive isotope.
  • The initial amount of the radioactive sample.
  • The elapsed time since the start of decay.