Asked by jezebel

Iodine-131 has a half life of eight days. What mass of iodine-131 would remain from a 20g sample after 32 days?
Answered by DrBob222
k = 0.693/t<sub>1/2</sub>

ln(No/N) = kt
No = 20g
N = solve for this
k from above.
t = 32 days.