The Half-Life of a Radioactive Isotope Is 1

question 159

Multiple Choice

The half-life of a radioactive isotope is 1.0 minute. In an experiment, the number of decay events was monitored in 1-minute intervals over a 5-minute period. What would you predict for the most likely observations if 50 decay events were observed in the first minute? In the second minute, ________ events were observed, and in the last minute, ________ events were observed.

• A)50; 50
• B)25; 3
• C)25; 25
• D)50; 100
• E)25; 13

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