Question

12. Predict How much of a sample of radioisotope remains after one half-life? After two half-lives?

Answer 1

3 4 of the original mass has decayed.

Step-by-step explanation:

After 1 half life, clearly HALF of the original isotope remains. And after TWO half-lives, a HALF + HALF of a HALF, i.e. 3 4 of the original mass has decayed.

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