AustralianPyromaniac Posted July 19, 2017 Share Posted July 19, 2017 Hey, I need some help with a Jennings white - Blue - Potassium Chlorate - 65 Copper (I) Chloride - 20Strontium Carbonate - 5Shellac - 10 (PyroData) Firstly, can CuCl be substituted with CuCl2 in a formula such as this? I would have thought CuCl would be too unstable to use anyway so would find no use. Is this a typo? Secondly, when CuCl or CuCl2 is used should it be in the anhydrous form or the hydrated form? Furthermore, if the hydrated form is to be used as I expect. Could the salt be weighed then dried in an oven to the anhydrous form so that stars such as these don't take weeks and weeks to dry, and possibly to give a better result? Has anyone tried this? Thanks for any tips. Link to comment Share on other sites More sharing options...
WSM Posted July 19, 2017 Share Posted July 19, 2017 (edited) Copper (I) chloride is a (more) stable dry powder, where copper (II) chloride absorbs lots of water from the atmosphere. The powdered copper (I) chloride should be ground as fine as possible to perform properly. WSM Edited July 19, 2017 by WSM Link to comment Share on other sites More sharing options...
Mumbles Posted July 19, 2017 Share Posted July 19, 2017 Copper (II) chloride is also corrosive to a whole bunch of metals we use in pyrotechnics as fuels as well as tools. Aluminum is attacked violently. Stainless steel is alright, but not totally impervious. Forms of iron and mild steel will be attacked. You'd want to use tools made of glass, plastic, or brass generally. Technically, I wouldn't call copper (I) chloride stable. It reacts with oxygen over time to get oxidized to copper (II). Due to it's low water solubility, it lasts for quite a while though. Pure copper (I) chloride is white. It takes on yellow and green hues as it gets oxidized over time forming copper (II) chloride and a complex hydroxide which is one of the couple compounds we refer to as copper oxychloride. Link to comment Share on other sites More sharing options...
rogeryermaw Posted July 19, 2017 Share Posted July 19, 2017 yeah......copper (I) chloride makes some really pretty blue stars but my experience with them hasn't been good. even aggressively sealed with n.c. lacquer, they were badly attacked by moisture. after about a week and a half, those fired from a star gun burned white. and those that i had not yet sealed and primed would no longer burn worth a damn. Link to comment Share on other sites More sharing options...
WSM Posted July 19, 2017 Share Posted July 19, 2017 (edited) Yeah, I guess our research out West (where the weather tends to be dryer) wouldn't be applicable generally to the rest of the country. I've seen incredibly deep blue stars demonstrated in Southwestern deserts back in the 1980's. I doubt those deep blues would look the same in humid air. WSM Edited July 19, 2017 by WSM Link to comment Share on other sites More sharing options...
WSM Posted July 19, 2017 Share Posted July 19, 2017 (edited) I believe the idea behind the original formula is to start with the copper salt most likely to produce the best color emitter (the monochloride of copper), and add a bit of strontium to shift the spectra away from green and more toward indigo. I see excellent potential for a good color, if the compatibilities work. Jennings-White is very intuitive and an avid researcher. WSM Edit: also it appears the original formula is meant to use either alcohol or acetone as a solvent, unless something more esoteric was planned. Edited July 19, 2017 by WSM Link to comment Share on other sites More sharing options...
AustralianPyromaniac Posted July 20, 2017 Author Share Posted July 20, 2017 Thanks for all the advice, I suppose I will have to use CuCl. I have some CuCl2 that I have made by reacting CuCO3 with HCl. How would I best go about reducing this to what I need? I know it can be reacted with copper or have sulphur dioxide bubbled through it but something strange on PyroData caught my eye. CuCl2 can be produced by the reaction between Copper (II) oxide (CuO),Copper carbonate (basic) (CuCO3), and/or Copper hydroxide (Cu(OH)2) and Hydrochloric acid. (Do not dilute the acid after dissolving otherwise Copper (I) Chloride will precipitate out) Chemical: Copper (II) Chloride (PyroData) Does the statement "Do not dilute the acid after dissolving otherwise Copper (I) Chloride will precipitate out" have any truth to it and by what mechanism would this occur? Could it be used to form the desired CuCl? Thanks again. Link to comment Share on other sites More sharing options...
RichardH08 Posted July 20, 2017 Share Posted July 20, 2017 (edited) Yes, that is more or less true. CuCl is insoluble in water, or very dilute HCl, but forms a soluble complex (H3CuCl4) with concentrated hydrochloric acid. You can make it by boiling a mixture of copper II oxide and copper turnings with excess concentrated hydrochloric acid until the solids have dissolved. Pouring the solution into a large volume of cold air-free water precipitates the CuCl. But you have to exclude air (or, more specifically oxygen) while separating the solids from the solution and drying them, so it really isn't very easy to do without fairly sophisticated apparatus. Oh, and I should add that boiling a concentrated hydrochloric acid solution is not a good idea unless you can do it in an effective fume cupboard. The vapour is corrosive and highly toxic, and can do a lot of damage to your lungs - or anything else it comes into contact with. Edited July 20, 2017 by RichardH08 Link to comment Share on other sites More sharing options...
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