What was the original mass of the Bismuth-212 sample if, after 121 seconds, it now weighs 2.64 grams, given that Bismuth-212 has a half-life of 60.5 seconds?(1 point)

Question

Responses

1.32 g
1.32 g

5.28 g
5.28 g

10.56 g
10.56 g

0.66 g

Answer 1

To solve this problem, we can use the equation for exponential decay:

final mass = original mass * (1/2)^(number of half-lives)

In this case, the final mass is 2.64 grams, the number of half-lives is t / half-life (121 seconds / 60.5 seconds = 2), and we want to find the original mass.

2.64 = original mass * (1/2)^2
2.64 = original mass * (1/4)
original mass = 2.64 * 4
original mass = 10.56 grams

Therefore, the original mass of the Bismuth-212 sample is 10.56 grams.

Answer 2

The chart displays the rate of radioactive decay for iodine-131.

According to the graph, what is the period of half-life for iodine-131?

(1 point)
Responses

16 days
16 days

24 days
24 days

8 days
8 days

4 days

Answer 3

Based on the given information, we cannot determine the period of half-life for iodine-131 from the chart. The options provided do not correspond to any information given in the question.