Sciencemadness Discussion Board

extraction of copper nitrate

symboom - 5-4-2016 at 14:12

Learning from the extraction of tetramine copper nitrate using chilled ethanol which worked really well strangly isopropanol and acetone both dont seem to work

I find the solvent must be souble in water to extract and the salt insouble in the solvent.

ive reacted strontium nitrate with copper sulfate
Removed the strontium sulfate percipitate and left with copper nitrate ive read it can be extracted with ether bit im afraid it might form peroxides does anyone if this is doable or have an idea of a better solvent

DraconicAcid - 5-4-2016 at 14:26

Anhydrous copper(II) nitrate is soluble in ethyl acetate, but I doubt that the hydrated form is.

annaandherdad - 6-4-2016 at 09:35

Why don't you just evaporate the water (after filtering the strontium sulfate) to get copper nitrate?

aga - 6-4-2016 at 13:01

Currently there is a 250ml beaker of aqueous copper nitrate in my lab which i attempted to recrystallise, twice.

It sits there because i do not know what to do with it.

Boiling the water too far (seems to be a very fine point) causes the whole thing to crystallise into a solid block with some slushy stuff that looks the same colour as basic copper carbonate on the bottom, and no supernatant liquid at all.

At a guess, water is not a suitable solvent for recrystallising copper nitrate.

Mabus - 8-4-2016 at 09:10

Quote: Originally posted by aga  
Currently there is a 250ml beaker of aqueous copper nitrate in my lab which i attempted to recrystallise, twice.

It sits there because i do not know what to do with it.

Boiling the water too far (seems to be a very fine point) causes the whole thing to crystallise into a solid block with some slushy stuff that looks the same colour as basic copper carbonate on the bottom, and no supernatant liquid at all.

At a guess, water is not a suitable solvent for recrystallising copper nitrate.

That green slush seems to have free nitric acid, cause when it touched my skin it instantly turned it yellow.

aga - 8-4-2016 at 11:15

pale blue ...

Texium - 8-4-2016 at 12:29

Copper(II) nitrate is deliquescent. You'll never get it to crystallize by letting it sit out in the open. The best way to grow good crystals of it is to boil it down until you have a concentrated solution and then put it in a desiccator over calcium chloride (and sodium hydroxide if there is excess nitric acid present), and let it sit there until it has all crystallized. Quickly transfer the crystals to a dry, airtight container for storage and only open it when you really need to get some out to use.

DraconicAcid - 8-4-2016 at 12:34

Quote: Originally posted by zts16  
Copper(II) nitrate is deliquescent. You'll never get it to crystallize by letting it sit out in the open.

Agreed. I had some lovely crystals forming after dissolving a copper penny in nitric acid, but upon sitting, the solution absorbed enough extra water to dissolve them all.

Mabus - 9-4-2016 at 00:18

Quote: Originally posted by aga  
pale blue ...

Well, yeah, mine is more like turquoise.

aga - 9-4-2016 at 07:45

Quote: Originally posted by zts16  
Copper(II) nitrate is deliquescent.

That would explain it then !

Nice one zts.

I'll put this pot in a dessicator bag and see what happens.

NeonPulse - 9-4-2016 at 16:05

It will take a long time! I had a small vial of the stuff in an hydroxide dessicator box and it took about a month to fully dehydrate. All that effort was a waste since over time I had opened it for use and it has turned to slush again. If Storing it dry is important then keep in the dessicator.

ave369 - 10-4-2016 at 04:48

Quote: Originally posted by Mabus  

That green slush seems to have free nitric acid, cause when it touched my skin it instantly turned it yellow.


Yep! I've got these results too. Green acidic mass. It's either excess nitric acid or the copper nitrate hydrolyzes.