How many days are required for a radioactive sample, with a half-life of 5.7 d and an initial activity of 1.07 × 10⁵ Bq, to decay to an activity of 100 Bq? A) 57 d B) 46 d C) 68 d D) 39 d

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Quizplus · Accepted Answer

The number of half-lives required for the activity to decay to 100 Bq is:log(100/1.07 × 10^5) / log(1/2) = 6.98Therefore, the number of days required is:6.98 * 5.7 d = 39.6 dRounding to the nearest whole number, the answer is 40 d.

How Many Days Are Required for a Radioactive Sample, with a Half-Life