The half-life of Palladium-100 is 4 days. After 12 days a sample of Palladium-100 has been reduced to a mass of 2 mg.
What was the initial mass (in mg) of the sample?
What is the mass 5 weeks after the start?
12 days is 3 half lives
2 --------- 4 --------- 8 -------- 16 mg initially
5 weeks = 5 x 7 = 35 days 35 days / 4days/half life = 8.75 half lifes
16 mg (1/2)8.75 = .03716 mg