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Elden [556K]
3 years ago
6

How many milligrams of a 20mg sample of cesium-137 remain after 60 years

Chemistry
1 answer:
andrey2020 [161]3 years ago
5 0
Cs -137 has a half life of about 30 years. If 60 years pass, there is two half lives passed so 1/2 * 1/2= 1/4. Take 1/4 and multiply it with the mass given:
(1/4)*20mg=5mg left
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