starlight Posted December 8, 2008 Share Posted December 8, 2008 some of you have never used the copper nitrate for use as a coloring agent in mixtures of blue flame? Link to comment Share on other sites More sharing options...
Steps Posted December 8, 2008 Share Posted December 8, 2008 (edited) I don't know? Maybe its troublesome to get. According to good ol' Wikipedia its hard to get it Anhydrous, holds onto water very well. But it decomposes before its supposed to loses all its water. Maybe its not that strong an oxidiser for some reason as well. Edited December 9, 2008 by TheLummox Link to comment Share on other sites More sharing options...
TurboSnail Posted December 8, 2008 Share Posted December 8, 2008 I don't know? Maybe its troublesome to get. According to good ol' Wikipedia its hard to get it Anhydrous, not that its that hydroscopic, but it decomposes before its supposed to lose its water. Maybe its not that strong an oxidiser for some reason as well. Using it as an copper donor in coloured flame, or as an oxidiser in normal pyrotechnic compositions will indeed be tricky, due to its hygroscopic nature, But it is soluble in MeOH >>>_@/" Link to comment Share on other sites More sharing options...
tentacles Posted December 8, 2008 Share Posted December 8, 2008 (edited) Turbo: If you can ever get it dry to start with.. I can't think of a more soluble/hydroscopic salt I've ever worked with. I can dry calcium chloride or copper sulfate on a table here in the wintertime, but copper nitrate just deliquesces. It is absurdly soluble - think 666g/100ml @ 100C. Or 138g/100ml at 0C. Edited December 8, 2008 by tentacles Link to comment Share on other sites More sharing options...
Steps Posted December 9, 2008 Share Posted December 9, 2008 Really, that's interesting. Beautiful blues can be made without it so i would guess don't waste your time with it. Link to comment Share on other sites More sharing options...
TurboSnail Posted December 9, 2008 Share Posted December 9, 2008 (edited) Turbo: If you can ever get it dry to start with.. I can't think of a more soluble/hydroscopic salt I've ever worked with. I can dry calcium chloride or copper sulfate on a table here in the wintertime, but copper nitrate just deliquesces. It is absurdly soluble - think 666g/100ml @ 100C. Or 138g/100ml at 0C. It will be soluble in methanol even if it contains water, making it free from water will indeed be hard. Maby adding a little methanol to the water containing nitrate and then driving the water of in a azeotrope kinda way might work out as a decent method of eliminating most of the water? I did not make my own, I got a bottle of it as a discount sort of thing when buying a shitload of other chems. Haven't really found any use fore it, but if I ever will it would probably be in solution as a copperdonor in coloured fireballs or something similar. *Dreaming of enlightening the sky with my hommade "Thermobarric Blue" fireball* >>>_@/" Edited December 9, 2008 by TurboSnail Link to comment Share on other sites More sharing options...
tentacles Posted December 9, 2008 Share Posted December 9, 2008 Turbo: You should check out the pics of the ghost mines at the last PGI convention. A whole row of huge blue ghost mines, wonderful color to them. There's a professional photographer who took some fantastics pictures but I can't remember his name or website right now.. I've been meaning to order some prints of them, actually. Link to comment Share on other sites More sharing options...
Richtee Posted December 9, 2008 Share Posted December 9, 2008 Turbo: If you can ever get it dry to start with.. I can't think of a more soluble/hydroscopic salt I've ever worked with. I can dry calcium chloride or copper sulfate on a table here in the wintertime, but copper nitrate just deliquesces. It is absurdly soluble - think 666g/100ml @ 100C. Or 138g/100ml at 0C.Christ- that's like me watching the end of "Wedding Singer" ;{) Link to comment Share on other sites More sharing options...
TurboSnail Posted December 9, 2008 Share Posted December 9, 2008 (edited) Thank you tentacles for the tip about Ghost mines, but I already seen them, and I moved on to trying to get the effect into shells by pouring ghost mine liquid into condoms that I put into paper hemispheres. With a hard break and the right fusing they will hopefully make nice blue fire balls in the sky I would like to make a batch of copper nitrate out of CuSO4 is there a simple way doing so? haven't realy thought about it for a while, I have been busy making Cu, Ba and Sr benzoates lately making wonderfull 2" ball shells <3 >>>_@/" Edited December 9, 2008 by TurboSnail Link to comment Share on other sites More sharing options...
optimus Posted December 9, 2008 Share Posted December 9, 2008 There's a professional photographer who took some fantastics pictures but I can't remember his name or website right now.. I've been meaning to order some prints of them, actually. I believe you're talking about tom:http://www.thecalderwoods.org/tom.htm Link to comment Share on other sites More sharing options...
Miech Posted December 9, 2008 Share Posted December 9, 2008 You can do that by a percipitation(?) reaction. When you dissolve your copper sulfate, and add a solution of a salt from which the sulfate salt of the positively charged ion is insoluble, you'll yield X sulfate and a solution of copper nitrate. For instance, if you add a barium nitrate solution, you will end up with barium sulfate and a copper nitrate solution. This would yield two usable chems, as barium sulfate is also used in pyrotechnics occasionally. The only drawback is that buying both chems is usually cheaper. Link to comment Share on other sites More sharing options...
Swede Posted December 9, 2008 Share Posted December 9, 2008 (edited) I've got 500 grams of copper nitrate (unopened) on my bench, and I can see the moisture inside the bottle. This begs the question - storage tips for hygroscopic materials like copper nitrate or ammonium nitrate. We all know about things like well-sealed bottles, but something like a "Do Not Eat" packet - if you plopped one of those in there, it'd probably give up what moisture it contained to the copper nitrate! War of the hygroscopics. Any thoughts? I think the simplest answer would be to sequester such chems in an HDPE bucket, itself sealed and protected with a moisture-absorbing packet. I'm tempted to force my hydrated copper nitrate into an anhydrous state with heat. At least that way, it's starting from scratch, and it'll be a long time before it turns into unuseable syrup. Edited December 9, 2008 by Swede Link to comment Share on other sites More sharing options...
Steps Posted December 10, 2008 Share Posted December 10, 2008 I'm tempted to force my hydrated copper nitrate into an anhydrous state with heat. At least that way, it's starting from scratch, and it'll be a long time before it turns into unuseable syrup. Only way to dehydrate completely is in a vacuum i doubt its really worth it. Link to comment Share on other sites More sharing options...
Miech Posted December 10, 2008 Share Posted December 10, 2008 That's not going to work on hydrous copper nitrate. There are so called ligands between the copper nitrate and the water molecules, which makes it impossible to remove the water by vacuum. Also, the water is likely to be closed in into the copper nitrate crystals, so only the surface would be exposed to the vacuum. It might work when you heat it under a vacuum however, but strongly doubt that. Link to comment Share on other sites More sharing options...
Mumbles Posted December 13, 2008 Share Posted December 13, 2008 Once copper nitrate becomes hydrated, it is impossible to dry completely. I think you can get it down to the dihydrate via vacuum heating. It will decompose into NOx before it gives up the last of it's water. The only way to get anhydrous copper nitrate is to prepare it. Copper metal and liquid N2O4 I believe is the method of choice. The method is published if anyone is actually interested. To keep chemicals like this dry, normally they'd be stored in a schlenk flask under vacuum or inert atmosphere in a glove box. Short of that, a dessicator and well sealed bottle should keep them for a while. The thing about adding methanol to a solution and driving it off as an azeotrope won't work. It holds onto water stronger than methanol can. I did think of something that has at least a minute potential of working. Say you dehydrated it down to the dihydrate, and made a methanol solution out of it. There is a finite exchange of ligands between the water and the methanol. You might be able to add some 3A molecular sieves to this to soak up the water. It might take a while, but it could theoretically work. Alternatively, one could use a stronger ligand than water to kick it off more rapidly, such as acetonitrile, or even a methanol solution of ammonia. A source to soak up water would be needed as well that was inert to said solvents. Link to comment Share on other sites More sharing options...
Swede Posted December 13, 2008 Share Posted December 13, 2008 Trying to stay on topic - my work area with my chems is maybe 10' X 4', really tight. That is a temperature-controlled room; summer or winter, it'll be between 60 and 80 F, good for long-term storage. Most actual work is done in a larger area. The physics behind cooling such a small room with a small AC unit is that the moisture skyrockets. OK, I'll fix that - I added a dehumidifier. Now it's winter, and the dehumidifier is working well, but the room - arid doesn't begin to describe it. The RH has to be 2%. When I walk in there, I am like Zeus, with long blue lightning bolts crackling off my fingers. Talk about a scary situation. Most of the chems are harmless, but there is maybe a kilo or two of BP in HDPE containers, and I refuse to get within 3 feet of them right now. I'm going to have to kill all the power to the room, leave the door open, perhaps spray water in there, before I'll be comfortable touching the BP containers. Conclusion: winter is a BAD time for static-sensitive materials. Flash? NO FRIGGING WAY. BE CAREFUL. Link to comment Share on other sites More sharing options...
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