Given a 800 mg sample of thorium-231 decomposes via beta emission with a half life of 25.5 hours, how long would it take, in days, for the sample to decay down to 25 mg?

231 0 231

th - > beta pa

90 - 1 91

800 mg / 25 mg

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The half-life of isotope X is 3 days, how long will it take for one half of 10g sample to decay

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Why is ac used instead of dc