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ELECTROPLATING

The Electroplating is the coating of an object, as for example a key with a metal layer. This one is used to protect the metal that is covered. In this case the key acts as cathode (negative pole) and the anode (positive pole) is a pure piece of the revestidor metal (copper wire). The electrolyte (liquid blue) contains water copper sulphate dissolved; whose ions cross the solution and cover the key. The metals have certain tendency to dissolve in the water, some more, others less. If we submerged a water zinc plate, some zinc atoms will lose two electrons (that is, two negative loads) and they will become ions (zinc) ++, with two positive charges. Nevertheless, those ions remain “patches? to the metal, because they do not want to move away of electrons (loads of different sign are attracted). But there is something takes the electrons, then if that those ions (zinc) ++ will happen to the solution!

SINCE ONE BECOMES

We prepare a copper sulphate solution, as the mentioned one in the experiment of crystals (it is possible to be prepared in cold and it is not necessary that is saturated). Now we took a piece from galvanized wire well clean and we submerged it in the solution. We will see that the wire is place setting by a copper layer of reddish color. What happened?

The blue solution that we used must its color to ions (it receives) ++. When we submerged the galvanized wire (that is of covered metallic zinc iron) the electrons that leave the zinc are taken by (it receives) ++ of the solution, the negative loads neutralize to the positives and metallic copper forms:

(it receives) ++ + 2 (electrons) - => receives metalist

And then if, the ions (zinc) ++ that are habian formed can happen to the solution. In summary: a little zinc dissolves and a little copper is deposited.

We can obtain a more permanent effect if we took a piece from copper wire and we submerged it in the solution next to a nail or another object that we wished to cover with copper.

Soon we took a great battery and we connected the positive pole to the wire of copper (called anode now) and the negative pole to the metal that we wished to cover with copper, as it is the case of the nail (that now cathode is called). After some hours we will notice that a fine copper layer has been deposited on the nail.