The half-life of ²¹⁸Po is 3.1 minutes.How much of a 155 gram sample remains after 0.40 hours?

Question

Quizplus · Accepted Answer

First, let's convert 0.40 hours to minutes:

0.40 hours * 60 minutes/hour = 24 minutes

Next, we need to determine the number of half-lives that occur during this time:

24 minutes / 3.1 minutes/half-life ≈ 7.7 half-lives

Now we can use the radioactive decay formula:

Amount remaining = original amount * (1/2)^(number of half-lives)

Plugging in the numbers:

Amount remaining = 155 g * (1/2)^(7.7) ≈ 0.72 g

Therefore, the best choice is C.

The Half-Life of 218Po Is 3