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Harrizon [31]
3 years ago
11

The half-life for the radioactive decay of calcium-47 is 4.5 days. how many half-lives have elapsed after 27 days?

Chemistry
2 answers:
Evgesh-ka [11]3 years ago
8 0
1 half-life      - 4.5 days
x half-lives   - 27 days

x=(1*27)/4.5=6
6 <span>half-lives have elapsed after 27 days.</span>
Pani-rosa [81]3 years ago
6 0

<u>Answer:</u> The number of half lives are 6

<u>Explanation:</u>

We are given:

Half life of a radioactive isotope = 4.5 days

Calculating the number of half lives after time has elapsed 27 days:

4.5 days have been elapsed time after 1 half life

So, 27 days must have been elapsed after = \frac{1}{4.5}\times 27=6 half lives

Hence, the number of half lives are 6

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