Q9 of 50 Page 1

After 24 hrs, only 0.125 gm out of the initial quantity of 1 gm of a radioactive isotope remains behind. What is its half life period?

Given:

Initial Mass of Radioactive Material, No = 1g


Mass of the material after decay, N = 0.125g


Time, t = 24 hours


To find: Half Life Period:





λ = 0.0866 hour-1


t1/2 = 0.693 / λ


= 0.693 / 0.0866


= 8 hours


Therefore the half-life period of the radioactive material is 8 hours.


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