A radioactive element decays exponentially according to the function Q(t) = Q0ekt
.If 100 mg of the element decays to 25 mg in 12 days, find the half-life of the element.
please help
2 answers
NEvermind got it its 6
100 * 1/2 * 1/2 = 25
12 days = 2 half lives
OR
1/4 = e^(12k)
ln(1/4) = 12 k
[ln(1/4)] / 12 = k
ln(1/2) = k t
t = ln(1/2) / {[ln(1/4)] / 12} = 6
12 days = 2 half lives
OR
1/4 = e^(12k)
ln(1/4) = 12 k
[ln(1/4)] / 12 = k
ln(1/2) = k t
t = ln(1/2) / {[ln(1/4)] / 12} = 6