two ways: remaining=12mg*(1/2)^13.5/4.5
you can do that by putting this in your google search window:12*(1/2)^(13.5/4.5)=
Nerd way:
remaining=12.5*e^(.693*13.5/4.5)=
and put that in your google search window
indium-115 has a half life of 4.5 hours, if you start with a 12.0mg sample of indium-115, how much will remain after 13.5 hours
2 answers
k = 0.693/t1/2
Solve for k and substitute into the below equation.
ln(No/N) = kt
No = 12.0 mg
N = ? mg
k = from above
t = 13.5 hrs
Solve for k and substitute into the below equation.
ln(No/N) = kt
No = 12.0 mg
N = ? mg
k = from above
t = 13.5 hrs