A freshly prepared sample of a radioactive isotope has an activity of 27.5 mCi. After 2.60...

Question

Question

A freshly prepared sample of a radioactive isotope has an activity of 27.5 mCi. After 2.60 hours, the activity is 21.0 mCi.

(a) Determine the half-life of the isotope. (h)

(b) How many nuclei of the isotope were contained in the freshly prepared sample? (nuclei)

(c) After how much time will the activity be 1.40 mCi? (h)

Answer 1

Answer #1

Answer 2

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