During nuclear explosion, one of the products is 90 Sr with half-life of 28.1 years. If 1μg of 90 Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.

Question

Philoid · Accepted Answer

Initial concentration, [R]_° = 1μg

Final concentration, [R]

Half-life t_1/2 = 28.1 yrs

Solution:

We know, t_1/2 = 0.693/k

Where, k – rate constant

⇒ k = 0.693/ t_1/2

⇒ k = 0.693/(28.1 yrs)

⇒ k = 0.0246 yrs^-1

Also,

If t = 10yrs, then, using the formula, we get,

⇒

⇒ = 0.7824μg

If t = 60yrs, then again, we get,

⇒

⇒ [R]₆₀ = 0.228 μg

∴ 0.2278μg of ⁹⁰Sr will be left after 60 years.

During nuclear explosion, one of the products is 90Sr with half-life of 28.1 years. If 1μg of 90Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.

During nuclear explosion, one of the products is ⁹⁰Sr with half-life of 28.1 years. If 1μg of ⁹⁰Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.