How Many Radioactive Atoms Are Present in a Sample That $\mu$

question 33

Multiple Choice

How many radioactive atoms are present in a sample that has an activity of 0.5 $\mu$ Ci and a half-life of 10 years? (1 curie = 3.7 * 10¹⁰ decays/s)

• A)9.5 * 10¹² atoms
• B)8.4 *10¹² atoms
• C)7.3 * 10¹² atoms
• D)6.5* 10¹² atoms
• E)2.7 *10⁵ atoms

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Definitions:

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