A drug is eliminated from the body in a first-order reaction with a rate constant of
7.6 x 10-3 / min at 37 oC. A patient is given 20 mg of this drug. What mass of the drug remains after 5 hours?
ln*(No/N) = kt
No = 20 mg
N = ?
k from the problem.
t = 5 hours.
Note: since k is given in per min and you want to know in 5 hours, I recommend you convert 5 hours to minutes.