The half-life of Palladium-100 is 4 days. After 12 days a sample of Palaladium-100 has been reduce to a mass of 6 mg. What was the initial mass of the sample? What is the mass 7 weeks after the start? : The half-life formula: A = Ao*2^(-t/h) Where A = resulting amt after t time Ao = initial amt t = time of decay h = half-life of substance

Find the initial amt Ao*2^(-12/4) = 6 Ao*2^-4 = 6 .0625*Ao = 6 Ao = Ao = 9.6 mg is the initial amt : Find the amt after 7*7 = 49 days A = 9.6*2^(-49/4) Enter above into a calc A = 0.00197 mg after 7 weeks