It is commonly known how to plate glass with silver using silver nitrate, ammonia and glucose.

With about the same effort, is there a way to plate glass with copper?


According to Chemical Demonstrations: A Handbook for Teachers of Chemistry (Vol 3, p226), a similar effect can be obtained for copper using copper(II) acetate, ammonia, and hydrazine.

The copper metal forms when hydrazine reduced and ammonia complex of copper(II) in basic solution. Hydrazine slowly reduces the complex to copper metal. When the surface of the test tube is very clean and wet, the copper metal will adhere to it, forming a copper-colored mirror.

The overall reaction that occurs in this demonstration can be represented by the equation $\ce{2[Cu(NH3)4]2+_{(aq)} + N2H4_{(aq)} + > 4OH-_{(aq)} -> 2Cu_{(s)} + N2_{(g)} + 4H2O_{(l)} + 8NH3_{(aq)}}$

Whether or not this can be described as "about the same effort" depends entirely upon the access you have to hydrazine, and to appropriate handling/safety equipment for working with the reagents. While hydrazine in solution is -- if I recall correctly, but I am not an MSDS -- considerably more stable than pure hydrazine, it's still toxic and corrosive (among other things).

  • $\begingroup$ Apologies if the Google Books preview for that page is not publicly viewable -- I'm currently on a university library network, so it's possible I have different access permissions; however, I've tried to reproduce enough to at least start to answer the question. $\endgroup$ – owjburnham Jan 24 '17 at 13:03
  • $\begingroup$ Thanks for the answer. Indeed, getting hydrazine is a little complicated to get if you don't work in chemistry, and is nasty stuff, too. It would be great if there were a way with chemicals easier to get... $\endgroup$ – sweber Jan 29 '17 at 0:05
  • $\begingroup$ Perhaps, hydrazine was picked in this case solely because it gives convenient products. So if you're not worried about impurities, other reducing agents -- perhaps even glucose -- might work? $\endgroup$ – owjburnham Mar 6 '17 at 17:14

Yes, it's quite possible.

Remember the Tollen's Reagent Silver mirror test? A Copper mirror can be created using Benedict's reagent but the glass surface must be first treated with Tin chloride sensitizer solution and Palladium chloride activator, when the Benedict's solution is heated with the reducing sugar a bright copper coat will be deposited on the glass


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