Electroplating (Oxford AQA IGCSE Combined Science Double Award)

What is electroplating?

• Electroplating is a process where the surface of one metal is coated with a layer of a different metal

• The anode is made from the pure metal you want to coat your object with

• The cathode is the object to be electroplated

• The electrolyte is an aqueous solution of a soluble salt of the pure metal at the anode

Electroplating a strip of iron with tin

• At the anode: Tin atoms lose electrons (are oxidised) to form tin ions in solution

• At the cathode: Tin ions gain electrons (are reduced) to form tin atoms which deposit on the strip of iron metal, coating it with a layer of tin

What is electroplating used for?

• Electroplating is done to make metals more resistant to corrosion or damage

  • E.g. chromium and nickel plating

• It is also done to improve the appearance of metals,

  • E.g. coating cutlery and jewellery with silver