The cheapest metal chromium

**piper184** · Sep 29, 2021, 07:56 PM

Yeah, I would like to see the reactions written out for each stage, maybe then I could understand it.
Thinking about how electrolysis for rust removal works, the rusty piece is put on the negative wire and the rust is reduced and the ions transported to the positive side. But that usually has a base for the electrolyte not an acid.
In this case, maybe the stainless bar in the first reaction was sending chrome to the spoon, then in the next reaction it was reversed to plate the target. I may have to dig out an old textbook and do some studying again.

**Kovanca Polock** · Sep 30, 2021, 06:06 AM

The stainless strip is not involved in the dissolution. From the spoon we get 3-valent chrom.

**cmarlow** · Oct 2, 2021, 07:56 PM

This might not be chrome, this might be nickel plating instead. Using nickel on both anode and cathode in a vinegar salt solution will force the nickel to move through the solution, where some of it will be converted to nickel acetate in the solution. The actual plating of the parts is fast because it uses the nickel in the solution instead of needing another nickle source, but it is good to use nickle electrodes to avoid contaminating the solution and either killing it or having weird colours appear in the plating. Higher voltages are ok for forming the solution faster, lower voltages in the plating process makes for a smoother plating job.
Nickel is a decent plating material even though it is not as hard as chrome and can be worn off over time.

**Kovanca Polock** · Oct 3, 2021, 03:37 PM

Nickel has a yellow shade and electrolyte of green

**cmarlow** · Oct 3, 2021, 07:31 PM

Stainless can have a lot of nickel in it. Nonmagnetic stainless is usually about 9% nickel.

**Kovanca Polock** · Oct 4, 2021, 04:12 AM

If we take into account the color of the electrolyte, it is chrome, since without using the heating of the liquid, the coating does not stick to the metal.