Question
Fluorine-18, which has 1/2 life of 110 minutes, is used in PET scans. If 100 mg of fluorine-18 is shipped @8AM, how many milligrams of the radioisotope are still active if the sample arrives at the lab at 1:30 pm?
Answers
DrBob222
k = 0.693/t<sub>1/2</sub>
ln(No/N) = kt
No = 18 mg
N = unknown
k from above.
t = minutes from 8 am to 1:30 pm.
OR, to keep the numbers a little more workable, you may wish to use t</sub>1/2</sub> in hours (110/60), then use t = hours from 8:00 AM to 1/:30 pm.
ln(No/N) = kt
No = 18 mg
N = unknown
k from above.
t = minutes from 8 am to 1:30 pm.
OR, to keep the numbers a little more workable, you may wish to use t</sub>1/2</sub> in hours (110/60), then use t = hours from 8:00 AM to 1/:30 pm.
Anonymous
0.50