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Offline Tutu_93

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Chemistry
« on: October 05, 2009, 07:55:27 pm »
I am stuck in a question in chemistry

A 1.39 g sample of hydrated copper (2) sulfate ( cuso4.xH2O)is heated until all the water of hydration is driven off.The anhydrous salt has a mass of 0.89 g . determine the formula of the hydrate ??

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Offline Ghost Of Highbury

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Re: Chemistry
« Reply #1 on: October 05, 2009, 08:05:14 pm »
First use the mass of the copper sulfate after all the water is gone to determine the moles of CuSO4

0.89/159.5 = 0.0055

The mass loss on heating can be used to determine the moles of water lost:

(1.39 - 0.89)/[(2 x 1) + 16] = 0.0278

Now determine the ratio of water to CuSO4

0.0278/0.0055 ~ 5
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(because its moles of water to moles of copper sulfate ratio)
« Last Edit: October 05, 2009, 08:17:58 pm by eddie_adi619 »
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Offline Tutu_93

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Re: Chemistry
« Reply #2 on: October 05, 2009, 08:07:11 pm »
Yaa i knw ..
 The actual answer is 5
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Offline Ghost Of Highbury

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Re: Chemistry
« Reply #3 on: October 05, 2009, 08:08:03 pm »
i edited it..check again
« Last Edit: October 05, 2009, 08:17:34 pm by eddie_adi619 »
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Offline Tutu_93

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Re: Chemistry
« Reply #4 on: October 05, 2009, 08:11:56 pm »
:D:D:D:D :D thhhhnnnnnk u
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Offline Ghost Of Highbury

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Re: Chemistry
« Reply #5 on: October 05, 2009, 08:12:32 pm »
okay.
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