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3 years ago

6

The original amount of radioactive substance is 10 grams. After several years, 2.5 gtams of the substance is remaining. How many

half-lives havr passed since the mass of the subtance was 10 grams?

1 answer:

nirvana33 [79]3 years ago

8 0

10/2=5 (one half life)
5/2=2.5(two half lives)

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