Thorium, a rare element in the earth's crust, has over seven

Last updated: 8/5/2022

Thorium, a rare element in the earth's crust, has over seven radioactive isotopes. Of of these 22790Th has a half-life of 18.68 days. Calculate the decay constant. _____d-¹ What percent of Th-227 will be left after 28 days? _____% When 15.5 % is left, how much time has passed? _____days