The half-life of carbon-11 is 20.3 minutes.How much of a 100.0 mg sample remains after 1.50 hours?

Question

Quizplus · Accepted Answer

First, let's find the number of half-lives that occurred in 1.5 hours.
1.5 hours = 90 minutes
90/20.3 = 4.43 half-lives
Now, we can use the half-life equation:
Amount remaining = (initial amount) x (1/2)^(number of half-lives)
Amount remaining = 100.0 mg x (1/2)^4.43
Amount remaining = 4.63 mg
Therefore, the answer is B) 4.63 mg.

The Half-Life of Carbon-11 Is 20