By comparing a sample's isotope ratio it is possible to see that after 6300 years, the original radioisotope had decayed to 25% of its original value. Estimate the half life of that particular isotope.

Question

Quizplus · Accepted Answer

The isotope decays to 25% of its original value in 6300 years, which means it has gone through two half-lives (since 100% -> 50% -> 25%). Therefore, the half-life is 6300 years / 2 = 3150 years, which is approximately 3200 years.

By Comparing a Sample's Isotope Ratio It Is Possible to See