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3 years ago

After two half-lives, a sample contains 10 grams of parent isotopes. How many grams of the parent isotope were present to start?

Chemistry

2 answers:

Lunna [17]3 years ago

8 0

T=2T
m=10 g

m=m₀2^(-t/T)

m₀=m/{2^(-2T/T)=m/2⁻²

m₀=10/2⁻²=40 g

40 grams

almond37 [142]3 years ago

8 0

Theirs a total of 39.9999G at the start

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<h3>Further explanation</h3>

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