A radioactive substance has a half-life of four months. 3/4 of the substance will decay in:
Correct answer: C. 8 months
- A. 6 months
- B. 12 months
- C. 8 months
- D. 16 months
Explanation
For each half-life, the quantity of the substance will be half. Starting from 100%3/4 of 100% = 75% which means 25% should remain.100% ---> 50% ---> 25%It took 2 half-lives to reach 25% which is 3/4th of the original value hence, the time taken is 4 x 2 = 8 months.
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Atomic nuclei contain protons and neutrons, with nuclear size, mass defect and binding energy describing their stability. The work covers alpha, beta and gamma decay, decay equations, half-life and decay rate, along with radiation safety and medical applications such as imaging, radiotherapy and tracers.
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