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Crank
3 years ago
8

Chromium-51 is a radioactive isotope used to label red blood cells to identify if they remain intact in the body. It has a half-

life of 27.7 days. If 0.25 mg is an approximate dose amount, how much remains after 83.1 days?
Chemistry
2 answers:
agasfer [191]3 years ago
5 0
\left[\begin{array}{cccc}0 \ days&27,7days&55,4days&\textbf{83,1days}\\&&&\\0,25mg&0,125mg&0,0625mg&\textbf{0,03125mg}\end{array}\right]
Cerrena [4.2K]3 years ago
3 0

Answer:

Amount of chromium-51 remaining after 83.1 days = 0.031 mg

Explanation:

Radioactive disintegration follows the exponential law which can be mathematically expressed as:

N(t)=N(0)e^{-0.693t/t1/2}------(1)

where N(0) = initial amount of the radioactive substance

N(t): radioactive substance left after time t

t1/2 = half life of the radioisotope

In the case of chromium-51:

N(0) = 0.25 mg

t = 83.1 days

t1/2 = 27.7 days

Substituting these values in equation (1) gives:

N(t)=0.25e^{-0.693*83.1/27.7} = 0.031 mg

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