A Certain Substance Has a Half-Life of 5

question 81

Multiple Choice

A certain substance has a half-life of 5.0 hours. How many nuclei of the substance are required to give an initial activity of 6.0 μCi? 1 Ci = 3.7 × 10¹⁰ Bq.

• A) 5.8 × 10⁹ nuclei
• B) 8.5 × 10⁸ nuclei
• C) 6.3 × 10⁸ nuclei
• D) 3.2 × 10⁹ nuclei
• E) 2.4 × 10⁹ nuclei

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