Strontium-90 is a long-lived fission product with a half-life of 28.0 years
CHEMISTRY · Subjective · US High School · Chemistry · Atomic Structure & Nuclear · Atomic Structure & Nuclear
Problem
Strontium-90 is a long-lived fission product with a half-life of 28.0 years. A sealed source originally contained 3.50 mg of pure 90Sr. At present the mass of undecayed 90Sr in the source is estimated to be 0.420 mg.
(a) Determine the time that has elapsed since the source was manufactured.
(b) Express this time in years and months (take 1 month = 30 days).