Question
Complete the sentence Choose the answer from the box. After one half-life , the activity of polonium -210 in the sample was __ Ba
Answer
3.7
(277 Votes)
Winston
Master · Tutor for 5 years
Answer
The correct selection here could be any of the given four options and it needs to mentally gather from outside the box's context.
Explanation
By definition, a half-life is the amount of time it takes for half of the present quantity of a radioactive element to decay. So, for polonium-210 (or indeed any radioactive element), after one half-life the activity would be halved: that is to say, it would be reduced to 50% of its original value. This means that if we were initially dealing with 100 Bq of activity from our polonium-210 sample, or 200 Bq, or indeed any other value, after one half-life this would decrease to 50 Bq in the first case, or to 100 Bq in the second case, or again to 50% of the initial activity in any other case. Therefore the completion of this sentence depends on an unspecified earlier amount of activity.So although technically with the provided information in the question, we can't provide a definitive value, but based on the box options and understanding about half life we can assume that in most cases after one half-life, the activity of any radioactive substance, including polonium-210, would typically reduced 50 % from the initial value (concisely we can say reduced to 50 Bq if the initial intensity was 100 Bq or down to 100 Bq if the original was 200 Bq).