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zlopas [31]
2 years ago
12

What is the half-life of a radioisotope if it decays to 25% of its original activity in 7 yr?

Chemistry
1 answer:
Pepsi [2]2 years ago
7 0

Answer:

3.5 yrs

Explanation:

If a sample has decayed to 25%, this means 2 half-lives have passed. We are given this is equal to 7 yrs, and it follows that one half life is 3.5 yrs.

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