Ok, I set up and experiment where I disolved NaCl into H2O until it was saturated. I then got a 9 Volt DC power supply and hooked up a Copper Anode and a Graphite Cathode. When the power is turned on, alot of gas bubble from the Graphite Cathode. I am assuming that this is H2. Relatively fewer bubbles are on the cathode. (Like hardly anything bubbling up at all.) The purpose of this experiment was to Create a Copper Salt. I was looking for CuCl2. Anyhow this is what happened. An orange precipitate came from the Anode. (arent most copper compounds green or blue?) Later in the reaction I noticed some seperation. The precipitate had floated on top of some water. By this time the water was a faint green color (obviously some sort of copper Ion or compound) I havnt isolated the green compound yet, but I am more focused on this orange precipitate. I conducted a flame test which told me that it was Sodium based. It isnt NaOH becasue that is white. I boiled off the water and was left with a dirty yet pure orange powder. I have no idea what this is. In a few days i will switch between graphite and copper cathodes and anodes to see what combinations will produce this precipitate. Until then, can anyone help try to figure out what this compound is? Thanks for any help I get, I know this was long
Copper chemistry is very complicated, especially, when both copper (I) and copper (II) chemistry are involved. At the link below, I give a description of a set of experiments I recently did with copper. These really puzzled me, but now I have quite some idea what is happening.
The yellow/orange stuff you get is a copper (I) compound. Under the given conditions, apparently the copper wire is not oxidized to copper (II), but to a copper (I) compound. More likely it is a copper (I) compound, contaminated with some copper (II).
I think that at the anode you have the following reaction:
Cu + OH(-) --> CuOH + e(-) (OH(-) from cathode reaction)
2CuOH --> Cu2O + H2O
In fact the two reaction can even better be described as formation of hydrous copper (I) oxide with composition Cu2O.xH2O. Cu2O.xH2O is orange/yellow. When contaminated with copper (II) it is dirty brown/yellow. Anhydrous Cu2O is brick red.
What I do not (yet fully) understand is the role of the chloride in the electrolysis experiment. When you perform electrolysis of a solution of NaOH, then you get O2 at a copper anode! When, however, quite some NaCl is mixed in, then you get the yellow copper (I) compound. Apparently, the Cl(-) plays an important role by means of complex formation, changing the redox-properties of copper considerably. In the presence of Cl(-), the oxidation state +1 of copper is strongly favoured (see links on webpage below).
This hydrous copper (I) compound can also be prepared chemically, without electrolysis.
Look at the pictures of the end of the webpage. Probably this brown/orange/yellow compound is very similar to what you have made by electrolysis.
http://www.woelen.nl/chem/exp0005/exp0005.htmThe yellow stuff is a copper (I) compound. When some concentrated HCl is added to the yellow stuff, then a dark solution is obtained, which becomes bright green on addition of some H2O2. The H2O2 oxidizes all copper (I) to copper (II), which in turn forms a green complex with chloride.
Wilco