Radioactive Elements Decay Via First-Order Kinetics

question 21

Multiple Choice

Radioactive elements decay via first-order kinetics. Consider a certain type of nucleus that has a rate constant of 1.0  10^-3 h^-1. A sample contains 5.0  10⁹ radioactive nuclides. Calculate the number of nuclides remaining after 39 days have passed.

• A) 64
• B) 7.8  10^-11
• C) 2.0  10⁹
• D) 5.0  10⁹
• E) 2.5  10⁹

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