1. Tardigrade
  2. Question
  3. Chemistry
  4. A radioactive isotope having a half-life of 3 days was received after 12 days. It was found that there were 3 g of the isotope in the container. Find the initial weight of the isotope, when it was packed (antilog 1.203 = 16)

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A radioactive isotope having a half-life of $3$ days was received after $12$ days. It was found that there were $3\, g$ of the isotope in the container. Find the initial weight of the isotope, when it was packed
(antilog $1.203 = 16$)

UPSEEUPSEE 2013

Solution:

No. of half-lives, $n=\frac{12}{3}=4$

Amount left after $n$ half-lives $=\frac{A_{0}}{2^{n}}$

$ 3 g =\frac{A_{0}}{2^{4}} $

or $3 g =\frac{A^{0}}{16}$

$\therefore \, A^{0}=48\, g$