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these ions then move towards the cathode and settle as a thin layer of metal. thus, the metallic object (cathode) is coated with a thin layer of metal from anode. electroplating iron nail with copper :
A +
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copper plate
iron nail
copper(II) sulphate solution electroplating iron nail with cooper i. the surface of the iron nail and the copper metal are rubbed with a sandpaper. ii. the iron nail and the copper metal are immersed in copper(II) sulphate solution as shown above. (the circuit is completed) iii. at the anode, the copper metal becomes thinner, this is because copper atoms at the anode release electrons to form copper cation. copper atom copper(II) ion + electrons iv. at the cathode, the surface of the iron nail is coated with a brown copper layer. this is because copper ions in the solution move towards the cathode to receive electrons and are discharged. copper metal is formed. copper(II) ion + electrons copper atom v. the copper metal formed settles on the surface of the iron nail. •
the aims of electroplating are to 1. prevent the metal from corrosion or rusting 2. make the metal look more attractive