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Ivan
2 years ago
5

How long will it take for a 40.0 gram sample of I-131 (half-life = 8.4 days) to decay to 1/16 its original mass?

Chemistry
1 answer:
Shtirlitz [24]2 years ago
6 0

Answer:

42 days

Explanation:

Half life = 8.4 days

Starting mass = 40.0 g

Time = ?

Final Mass = 1/16 * 40 = 2.5 g

First Half life;

Remaining mass = 40 / 2 = 20g

Second Half life;

Remaining mass = 20 / 2 = 10g

Third Half life;

Remaining mass = 10 / 2 = 5g

Fourth Half life;

Remaining mass = 5 / 2 = 2.5g

Time = Number of half lives * Duration of half life = 5 * 8.4 = 42 days

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Answer: The substance is neutral

Explanation:

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Blue litmus paper in acid turns red when placed in a basic or neutral solution it remains blue. From this it can be concluded that the solution is neutral.

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I believe the best answer to that question wud be D. I cud b wrong 
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How many grams of calcium chloride are dissolved in 5.65 liters of a 0.11 m solution of calcium choride?
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