A 4.0 g sample of Ra-226 decays to 1.0 g.If the half-life of Ra-226 is 1620 years,how much time has elapsed?

Question

Quizplus · Accepted Answer

Since the half-life of Ra-226 is 1620 years, we can use the formula for radioactive decay:

N=N0(1/2)^(t/T)

where N is the final amount (1.0 g), N0 is the initial amount (4.0 g), t is the time elapsed, and T is the half-life (1620 years).

Solving for t, we get:

t = T*log(N/N0)/log(1/2) = 3240 years

A 40 G Sample of Ra-226 Decays to 1