A 32g radioactive element decays and remains 2g after 60 days. What is the half- life of radioactive element?
Correct answer: D. 15 days
- A. 2 days
- B. 6 days
- C. 10 days
- D. 15 days
Explanation
The time taken for half of the original population of radioactive atoms to decay is called the half-life. 32/2=16 16/2=8 8/2=4 4/2=2 60/4=15 days
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About Half-life and Rate of Decay
Half-life is the time required for half the unstable nuclei in a sample to decay, and it remains constant for a particular radioactive nuclide. Questions use the exponential decay law, decay constant, activity, remaining quantity and mean life. Radioactive decay is random for individual nuclei but predictable for large samples.
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