the half life of radioactive isotope radium 226 is 1600 years. suppose we have a sample that has a mass of 20 mg
Answer: 50.1 micrograms.
Explanation: A sample of radium-226 with an initial mass of 20 mg was analyzed. The half-life of radium-226 is 1600 years. Using the exponential decay formula for radium-226, we calculated the amount of radium-226 remaining after 3200 years to be approximately 1.33 x 10^18 atoms, which corresponds to a mass of 50.1 micrograms.