far2g0n3
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chromate to dichromate
If you have potassium chromate in 5% sol'n, how do you turn it into dichrimate?
*edit thank you..
[Edited on 19-7-2015 by far2g0n3]
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Texium
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Huh? This entire thread
makes absolutely no sense. Where does the formate come into it?
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Aqua-regia
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pls choose other topic instead organic chemistry. this is an absolutelly beginning topic
acidify your yellow solution to get dichromate ions.(orange colour)
2CrO4 2- +2H+ = Cr2O7 2- +H2O
[Edited on 19-7-2015 by Aqua-regia]
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far2g0n3
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Thanks for the reply. I read that acidify made a mixture if di and mono chromate but I didn't get his much was to be used.
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Aqua-regia
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Ok, if you are beginner (are you) need to know, cromate and mainly dichromate are very nasty chemicals. In Europe is strong recommended not, or
forbidden to use dicromate in high school education.
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aga
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Chromates aren't for Beginners really, whereas this thread is.
Chromates will kill you if you have no respect for them, or you'll pour them down the drain or in a field where they'll kill something else.
Acidifying Potassium Chromate will oxidise it to the Dichromate.
Personally i reduced potassium dichromate to chromate for some titration or other (ethanol ?) which turned out to be a totally pointless exercise, as
the dichromate would have been fine in a basic solution.
What do you need yours for ?
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j_sum1
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Quote: Originally posted by aga  | <snip>
Acidifying Potassium Chromate will oxidise it to the Dichromate.
Personally i reduced potassium dichromate to chromate <snip> |
Only it is not oxidation (or reduction). Both Cr2O7(2-) and CrO4(2-) have chromium in the +6 oxidation state.
It's been a good weekend for me and chromium. 
[Edited on 19-7-2015 by j_sum1]
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Polverone
Now celebrating 21 years of madness
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Thread Moved
19-7-2015 at 15:13 |
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