If 0.4 curie be the activity of 1 gram of radioactive samples whose atomic mass is 226, then what is the half life period the sample? (1 curie `= 3.7 xx 10^(10) "dis" "sec"^(-1))`

Options

A. `1.2 xx 10^(11)` sec
B. `1.8 xx 10^(11)` sec
C. `1.2 xx 10^(10)` sec
D. `1.8 xx 10^(10)` sec

Answer

a

Explanation

Rate if decay `= (0.693)/(t_(1//2)) xx (w)/(A_(w)) xx 6.023 xx 10^(23)`
`0.4 xx 3.7 xx 10^(10) = (0.693)/(t_(1//2)) xx (1)/(226 xx 6.023 xx 10^(23)`
`t_(1//2) = 1.2 xx 10^(11)` sec'