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3 years ago

12

How do you work out how many atoms there are in a isotope?

1 answer:

GalinKa [24]3 years ago

4 0

206Pb = 1.342 x10^22 atoms

<span>To find the number of atoms, you must first find the number of moles. If 238U is 238.029g/mol, and we have 1.75 grams, how many moles is that? 1.75 divided by 238.029 = 0.007352045 moles. To find the number of atoms in 0.007352045 moles, you multiply by a mole: </span>
<span>0.007352045 x 6.02 x 10^23 = 4.426 x10^21 atoms. </span>

<span>Same procedure for 206Pb: </span>
<span>4.59 divided by 205.97446 = 0.022284316 moles </span>
<span>0.022284316 x 6.02 x 10^23 = 1.342 x10^22 atoms. </span>

<span>Hope that helps you!
https://answers.yahoo.com/question/index?qid=20100331153014AAoMXcu
</span>

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2 years ago

A man does 4,780 J of work in the process of pushing his 2.70 103 kg truck from rest to a speed of v, over a distance of 25.5 m.

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Answer:

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2 years ago

Suppose that a public address system emits sound uniformly in all directions and that there are no reflections . The intensity a

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Answer:

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Explanation:

The definition of the intensity in terms of power is given by:

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and to the second location we have:

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Now, we can divide each intensity to find the second intensity.

$\frac{I_{2}}{I_{1}}=\frac{\frac{P}{4\pi 78^{2}}}{\frac{P}{4\pi 22^{2}}}$

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$I_{2}=2.39*10^{-5} W/m^{2}$

I hope it helps you!

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