Question

If 250 mg of a radioactive element decays to 200 mg in 36 hours, find the half-life of the element. (Round your answer to the nearest whole number.)

Answer 1

Explanation:

200 = 250 (1/2)^x

200/250 = (1/2)^x LOG both sides

LOG (.8) = x LOG(1/2)

.321928 = x this is .32198 of a half life

.32198 x = 36 where x = half life

x = 111.8 = 112 hr half life