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shutvik [7]
3 years ago
12

If you have 222 g of radioisotope with a half-life of 5 days, how much isotope would remain after 15 days?

Chemistry
1 answer:
Dima020 [189]3 years ago
7 0
If the half life is 5 days, you would have to divide 222 by 2 3 times.
so 222/2 =111g
111/2 = 55.5g
55.5/2 = 27.75g

after four half life the mass would be
27.75/2
13.875g

the percent would be
13.875/222
= 6.25%
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