The half-life of 131I is 8.04 days.
(a) Convert the half-life to seconds.
(b) Calculate the decay constant for this isotope.
(c) Convert 0.350 μCi to the SI unit the becquerel.
(d) Find the number of 131I nuclei necessary to produce
a sample with an activity of 0.350 μCi.
(e) Suppose the activity of a certain 131I sample is
6.10 mCi at a given time. Find the number of half-lives the sample
goes through in 40.2 d and the activity at the end of that period.
(Enter your answer for the number of half-lives to at least one
decimal place.)
half-lives | |
mCi |
We know the emperical formulae for the decay constant, half life, activity of sample etc. So we just need to put the values and take care of the calculations.
The half-life of 131I is 8.04 days. (a) Convert the half-life to seconds. (b) Calculate the...
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