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3 years ago

5

After 3 days a sample of radon-222 has decayed to 58% of its original amount.(

1 answer:

iren2701 [21]3 years ago

3 0

Half-life = [elapsed time * log (2)] / [log (begng amt / endg amt)]
half-life = (3 days * 0.30102999566) / log (1 / .58)
<span>half-life = 0.903089987 / log </span> (<span> <span> <span> 1.724137931)
</span></span></span>half-life = <span>0.903089987 / 0.23657200643</span>
half-life = <span> <span> <span> 3.8174 days

Source:
http://www.1728.org/halflife.htm

</span></span></span>

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