Jor - 25-1-2010 at 04:05
If anyone is interested, this is a very nice experiment.
First clean a test tube with boiling nitric, rinse with water, boil with dil. NaOH, rinse with distilled water again, and without letting it dry, add
an almost saturated solution of copper acetate, without solid particles in it.
Now add aq. ammonia, until all initially formed precitipate redissolves, giving a dark blue solution. To this add 0,15mL hydrazine hydrate (for every
5mL of copper acetate solution, I used about 0,3mL of a 55% hydrazine hydrate solution), shake very briefly and put the test tube in a 80-90C water
bath immediately. When this is done a copper mirror forms. Pictures:
http://amateurchemie.nl/viewtopic.php?f=20&t=404
Other copper salts and hydrazine salts do not work accordin to this article:
http://books.google.nl/books?id=btNF9aLXtPcC&pg=PA226&am...
But you can make hydrazine hydrat with hydrazine sulfate and barium hydroxide (or possibly carbonate).
a_bab - 25-1-2010 at 04:53
This is really beautiful and a good way to get the REAL copper color for my element collection.
aonomus - 25-1-2010 at 07:02
Do you think that this method could be repurposed to form a coating thick enough to allow further electroplating? How resilient is the copper to
mechanical force? Silver from Tollens reagent is a real PITA to clean off glassware, but its hard to plate anything onto, while copper on the other
hand can be attacked by other acids, and also can be plated on to...