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Arada [10]
1 year ago
7

Calculate the percent activity of the radioactive isotope strontium-89 remaining after 5 half-lives.

Chemistry
1 answer:
maria [59]1 year ago
5 0
The answer to this question would be: 3.125%

Half-life is the time needed for a radioactive molecule to decay half of its mass. In this case, the strontium-89 is already gone past 5 half lives. Then, the percentage of the mass left after 5 half-lives should be:
100%*(1/2^5)= 100%/32=3..125%
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Explanation:

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2 moles of chromium can react to 3 moles of iron (II) nitrate in order to produce 2 moles of iron and 2 moles of chromium nitrate.

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Iron changed the oxidation state from +2 to 0

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This is an incomplete question, the given sketch is shown below.

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Explanation:

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