Question

D. 0.5 g Sample of 201 TI decays to 0.0788 g
in 8 days. What is its half life?​

Answer 1

The half life of the sample of 201Tl is 3 days.

Given that, initial amount = 0.5gm and amount after 8 days is 0.0788gm.

So, N = 0.5gm and N' = 0.0788gm t' = 8 days.

Let half life period be t days.

As, t = (8 * ln 2)/[ln (N/N')]

= (8*0.693)/[ln (0.5/0.0788)]

= 5.544/1.848

= 3 days.

This is the half life.