Find the activity of 1 g sample of `""_(84)Po^(210)`. The half-life of `""_(84)Po^(210)` is 138 days.

Explanation

T=138 days `=138 xx 24 xx 60s`
N=Number of atoms in 210 g `=6.023 xx 10^(23)`
N=Number of atoms in 1g `=(6.023 xx 10^(23))/210`
Activity `=R =-(dN)/(dt) = lambda N`
`=0.693/T_(1//2).N [therefore lambda=0.693/T_(1//2)]`
`=(0.693 xx 6.023 xx 10^(23))/(138 xx 24 xx 60 xx 60 xx 210) = 1.66 xx 10^(14)` Bq