Answer to Question #94319 in Inorganic Chemistry for Maria Rizwan

Question

Naturally occurring cobalt consists of only one isotope 59Co, whose relative atomic mass is 58.9332. A synthetic radioactive isotope of cobalt 60 Co has relative atomic mass 59.9338, is used in radiation therapy for cancer. A 1.8536g sample of cobalt has an apparent "atomic mass" of 58.9901. Find the mass of 60 Co is this sample?

Answer 1

If mass of 59Co is 58.9332 and mass of 60Co is 59.9338 and  sample of cobalt has an apparent "atomic mass" of 58.9901 than percent of 60Co in sample is

58.9332(1-x)+59.9338x = 58.9901

x≈0.0568659

Percent of 60Co is 5.687%

Mass of 60Co in sample is 0.1054 g