Electroplating Copper Chromium Alloy Deposit

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(to provide context, hopefully helping readers more quickly understand the Q&A's)

It is far more often the case that you can't electrodeposit a given alloy than that you can :-(

Why? Consider for example a student's lemon battery where a copper penny and a zinc coated nail are inserted into the conductive lemon juice and connected. A voltage of about 1.0 volts is generated as the copper pulls electrons from the zinc, causing the zinc to lose electrons and turn from metal to positively charged ions that dissolve into the acidic juice.

Now imagine trying to electrodeposit brass (copper-zinc) in this electrolyte. No sooner would an atom of zinc plate out as metal, than a copper ion next to it would steal its electrons, turning the zinc atom into a positively charged ion which dissolves again ... so your electrodeposit will be almost pure copper instead of brass.

There are some complexing tricks that can make plating of certain alloys (including brass) possible, but in general it's tough and usually it's impossible.