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A radioactive isotope having a half - life period of 3 days was received after 12 days. If 3 ~g of the isotope is left in the container, what would be the initial mass of the isotope ?

Options

  1. A12 ~g
  2. B36 ~g
  3. C48 ~g
  4. D24 ~g

Correct answer

C. 48 ~g

Step-by-step solution

Given t_ 1 / 2 =3 Total time T =12 No. of half lives (n)= 12 3 =4 ( 1 2 )^n= N N _ o ( 1 2 )^4= 3 ~N _ o 3 ~N _ o = 1 16 ~N _ o =48 ~g

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