A radioactive isotope used in a Jamaican hospital has a half-life of 6 hours. If the initial activity is 800 Bq, what will be the activity after 18 hours?

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Question

A radioactive isotope used in a Jamaican hospital has a half-life of 6 hours. If the initial activity is 800 Bq, what will be the activity after 18 hours?

Accepted Answer

100 Bq — Award 1 mark for correct calculation. 18 hours = 3 half-lives. 800 → 400 → 200 → 100 Bq. B is incorrect — this represents only 2 half-lives. C is incorrect — this represents only 1 half-life. D is incorrect — this would represent 4 half-lives (24 hours).

Answer

50 Bq

Answer

400 Bq

Answer

200 Bq

Answer

100 Bq

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