ionic bond
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heating CuSO4.xH2O
Hi
when we heat CuSO4.xH2O
CuSO4.xH2O --------> CuSO4+ xH2O
If 36 g of CuSO4.xH2O gives 15.88 g of H2O.
Calculate x
I tried to calcualte it like this:
36/(195.5+18x) = 15.88/18x
x = 7
is that right?
thanks
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vulture
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Don't think that is right...
Try it this way:
36g - 15.88g = 20.12g CuSO4 --> calculate how many moles CuSO4 this is.
15.88g/18g = 0.88 mole H2O
divide 0.88 mole H2O through # moles of CuSO4 et voila...
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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ionic bond
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Hi
but we don't know if all of the CuSO4.xH2O will react!!
[Edited on 22-7-2004 by ionic bond]
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chemoleo
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Oh, if you heat it up enough, surely all the CuSO4x xH2O will decompose.
I would also do it vulture's way- you want the ratio of the moles H2O versus the # of moles CuSO4 .
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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Magpie
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That all the water leaves the salt is implied in your statement of the problem:
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CuSO4.xH2O --------> CuSO4+ xH2O
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The single most important condition for a successful synthesis is good mixing - Nicodem
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vulture
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If you don't heat the reaction untill it's completed, it's impossible to calculate it.
Furthermore, completion of the reaction can be easily observed visually.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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ionic bond
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Don't you see that the results are the same!
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vulture
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Indeed, you are right, 7 is the result.
I didn't calculate it through because this is in the beginnings section.
I'm not aware of the existance of a heptahydrate, but it could be possible.
Another possibility is that your pentahydrate was wet, eg not properly dried/crystallized.
It would be a fluke though to get a nice seven if it was residual water.
One shouldn't accept or resort to the mutilation of science to appease the mentally impaired.
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