tylerngo
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Green Cobalt(II) hydroxide in D2O
I reacted Potassium metal with Deuterium oxide in order to yield a basic solution of Potassium deuteroxide. I then added Cobalt(II) chloride to
precipitate Cobalt(II) deuteroxide. It has been 2 days already and my precipitate is still green. Why do you think this is?
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j_sum1
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Thread Moved 11-10-2018 at 05:15 |
fusso
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Why you want to make Co(OD)2?
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Boffis
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How did you add the cobalt chloride? If it was in aqueous solution or even as the solid hydrated salt will you not get hydrogen/deuterium
partitioning? Or did you use a more sophisticated aprotic solvent system or anhydrous CoCl2 dissolved in deuterium oxide? Without more details we
can't really help you. Furthermore how do you know your product is simple Co(OH)2?
natural cobalt calcium hydroxide arsenate (cobaltaustinite) is dark green whereas hydrated cobalt calcium arsenates are deep pink to magenta coloured.
Its all to do with what ligand the cobalt is coordinated with. I would be very surprised if deuterium oxide caused a significant chromatic shift
compared to water. I think that it is more likely that the potassium deuteroxide solution is so concentrated that you have precipitated an anhydrous
product which is inherently green.
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