Describe the decay of a radioactive substance in terms of its decay constant and half-life
Use the radioactive decay law to estimate the age of a substance
Explain the natural processes that allow the dating of living tissue using 14C
Practice!
Practice 12.3.1
The isotope, tritium, has a half-life of 12.3 years. Assume we have 10 kg of the substance. What will be the decay constant?
A. 5.6 x 10–2 s–1
B. 5.6 x 108 s–1
C. 3.2 x 107 s–1
D. 1.8 x 10–9 s–1
E. 1.6 x 106 s–1
Check your answer: D. 1.8 x 10–9 s–1
Practice 12.3.2
The isotope, tritium, has a half-life of 12.3 years. Assume we have 10 kg of the substance. What will be the initial decay rate, at t = 0 (in decays/s)?
A. 1.09 x 1014 decays/s
B. 1.8 x 10–9 decays/s
C. 5.6 x 108 decays/s
D. 3.6 x 1018 decays/s
Check your answer: D. 3.6 x 1018 decays/s
Practice 12.3.3
The isotope, tritium, has a half-life of 12.3 years. Assume we have 10 kg of the substance. How much tritium will be left after 30 years?
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