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Nesterboy [21]
3 years ago
14

How long does it take for 87.5 % of each isotope to decay?

Chemistry
1 answer:
Zolol [24]3 years ago
7 0

Answer:

Kr-73 = 23.625 sec

Kr-74 = 10.0625 minutes (603.75 seconds)

Kr-76 = 12.95 hours (777 minutes)

Kr-81 = 1.8375 * 10^6 years

Explanation:

What you do is multiply each of those amounts by 7/8.

27 * 7/8 = 189/8 = 23.625

23/2 * 7/8 = 161/16 = 10.0625

74/5 * 7/8 = 518/40 = 259/20 = 12.95

210000 * 7/8 = 1470000/8 = 183750 = 1.8375 * 10^6

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Select all of the items that are true about a sample of water vapor at 101°C as it cools.
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<h3><u>Answer;</u></h3>

A) Its temperature will fall continuously until it condensed into a liquid.

<h3><u>Explanation</u>;</h3>
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3 years ago
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Imagine mixing 1 tablespoon of Epsom salt with 2 cups of ammonia. How much precipitate would be produced? Describe the amount of
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Answer:

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3 years ago
A sample of hydrated copper (II) sulfate (CuSO4•nH2O) is heated to 150°C and produces 103.74 g anhydrous copper (II) sulfate and
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Answer:

5

Explanation:

Firstly, we convert what we have to percentage compositions.

There are two parts in the molecule, the sulphate part and the water part.

The percentage compositions is as follows:

Sulphate- (103.74)/(103.74 + 58.55) × 100% = apprx 64%

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