A radioactive substance with a half-life of 3.0 days has an initial activity of 2400 Bq.What is its activity after 6.0 days?
A)1200 Bq
B)1800 Bq
C)600 Bq
D)300 Bq
E)150 Bq

Question

Quizplus · Accepted Answer

Half-life of the substance = 3.0 days
Initial activity = 2400 Bq
After 1 half-life, activity = (1/2) x 2400 Bq = 1200 Bq
After 2 half-lives (i.e. 6.0 days), activity = (1/2)^2 x 2400 Bq = 600 Bq
Therefore, the answer is (C) 600 Bq.

A Radioactive Substance with a Half-Life of 3