A radioactive sample has a half-life of 2 days. Its mass of the radioactive nuclide is 240 g. How much remains after 6 days?
Answer and explanation
Correct answer: B. 30 g
- Step 1: The number of half-lives is .
- Step 2: Remaining mass g.
Answer
30 g.
Why not the others: 40 g: it divides by rather than halving times. 60 g: it halves one time too few. 15 g: it halves one time too many.
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