An Isotope of Tc Having a Half-Life of 6

question 18

Multiple Choice

An isotope of Tc having a half-life of 6.0 h is used in bone scans. If a certain amount of this Tc is injected into the body, how long does it take for its initial decay rate to decrease BY 99%?

• A) 0.060 h
• B) 3.3 h
• C) 33 h
• D) 40 h
• E) slightly more than a month

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