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Question

The half-life of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mass. Starting with 145 grams of a radioactive isotope, how much will be left after
5 half-lives? Round your answer to the nearest gram.

 

Answer 1

A = a₀(0.5)^t

A = 145(0.5)⁵

A = 145(0.03125)

A = 4.53125

 

To the nearest gram you have 5.