Iodine-131 has a half-life of 8 days. In how many days will a 1 kg sample of iodine-131 decay and reduce to 0.0625 kg of iodine-131?
a) 8 days
b) 16 days
c) 24 Days
d) 32 Days

Question

Iodine-131 has a half-life of 8 days. In how many days will a 1 kg sample of iodine-131 decay and reduce to 0.0625 kg of iodine-131? 
a) 8 days
b) 16 days
c) 24 Days
d) 32 Days

anonymous · Answer

i do not really know about this but you could read on it from http://www.xtremepapers.com/revision/a-level/physics/nuclear_physics.php

aaronq · Answer

Find the decay constant, k:

$$t _{1/2}=\frac{ \ln2 }{ k }$$

Solve to t, time.

$$A=A _{0}e ^{-kt}$$

A= amount after time elapsed
Ao=initial amount
k= decay constant
t= time