The decay equation is of the form
where
m(t) = the mass remaining after t minutes
m₀ = the initial mass
k = constant
Because the half-life is 3 minutes, therefore
Therefore
-3k = ln(0.5)
k = ln(0.5)/(-3) = 0.231
Because m₀ = 16 mg, the time, t, for the mass to decay to 1.0 mg is given by
Answer: 22 min (nearest integer)
where
m(t) = the mass remaining after t minutes
m₀ = the initial mass
k = constant
Because the half-life is 3 minutes, therefore
Therefore
-3k = ln(0.5)
k = ln(0.5)/(-3) = 0.231
Because m₀ = 16 mg, the time, t, for the mass to decay to 1.0 mg is given by
Answer: 22 min (nearest integer)