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Chemistry
Chemistry
Problem
A pure sample of a radioactive isotope is allowed to decay for a time equal to two half-lives. Which fraction of the original nuclei has NOT yet decayed? a)
1
2
\dfrac{1}{2}
2
1
b)
1
4
\dfrac{1}{4}
4
1
c)
1
8
\dfrac{1}{8}
8
1
d)
3
4
\dfrac{3}{4}
4
3
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