After two half-lives have passed, the ratio of a radioactive element to its daughter element is
A)0 to 4.
B)1 to 4.
C)1 to 3.
D)1 to 2.
E)1 to 1.

Question

Quizplus · Accepted Answer

After two half-lives, the original radioactive element will have decayed to 25% of its original amount (halved twice), while the daughter element will have accumulated to 75% of the final amount (100% - 25%). Therefore, the ratio of the radioactive element to its daughter element is 1 to 3.

After Two Half-Lives Have Passed, the Ratio of a Radioactive