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Ray Of Light [21]

3 years ago

10

Thorium-234 has a half-life of 24.1 days. How much of a 100-g sample of thorium-234 will be unchanged after 48.2 days?

2 answers:

oee [108]3 years ago

7 0

Half-life means that the matter degrades by 50% at each interval. 48.2 days is 2 intervals.

So, it would go down by 50% in the first interval, making it 50g. Then it would go down by another 50% from there, making the final amount of undecayed thorium-234 25g.

musickatia [10]3 years ago

5 0

25G is the answer for sure.

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A 1.000 g sample of an unknown hydrate of cobalt chloride is gently dehydrated. The resulting mass is 0.546 g. The cobalt is iso

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Answer:

Explanation:

From the 1 g sample you have:

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$n_{Co}=\frac{0.248 g}{58.9 g/mol}=4.21*10^{-3}mol$

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