Question

The function gives the mass, m, of a radioactive substance remaining after h half-lives. Cobalt-60 has a half-life of about 5.3 years. Which equation gives the mass of a 50 mg cobalt-60 sample remaining after 10 years, and approximately how many milligrams remain?

1) 0 mg
2) 0.05 mg
3) 13.5 mg
4) 25 mg

Answer 1

The correct answer is Option 3) 13.5 mg.The equation for the mass of a cobalt-60 sample after a certain number of years can be used to calculate the amount of cobalt-60 remaining after 10 years.

Step-by-step explanation:

The equation that gives the mass of a 50 mg cobalt-60 sample remaining after 10 years is:

m = 50 mg * (1/2)(10/5.3)

Using this equation, we can calculate the approximate amount of cobalt-60 remaining:

m = 50 mg * (1/2)(10/5.3) = 13.5 mg

Therefore, approximately 13.5 mg of cobalt-60 remain after 10 years. The correct answer is Option 3) 13.5 mg.