The half. life of a radioactive isotope is 8 days. If a sample initially contains 106 atoms, how many atoms remain after 24 days?
Correct answer: A. 1.25 x 10^5
- A. 1.25 x 10^5
- B. 2.50 x 10^5
- C. 5.00 x 10^5
- D. 7.50 x 10^5
Explanation
The number of half. lives in 24 days is 24/8 = 3. The number of atoms remaining is N = No × (1/2) , where N = 10 and n = 3. Thus, N = 10 × (1/2) = 10 × 1/8 = 1.25 × 10 atoms.
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