Ions are the atoms or molecules which are electrically charged. The charge can be of two types namely positive and negative. Thus, there are two types of ions namely cations (positively charged) and anions (negatively charged).

A liquid that conducts electricity due to the presence of ions is called an electrolyte. For example: tap water, salt solution, lemon juice, and copper sulphate. Note: A liquid which is incapable of conducting electricity is known as non-electrolyte. For example: honey, distilled water.

The production of a chemical reaction by passing an electric current through an electrolyte is called an electrolysis. Electrolysis brings about a chemical change in an electrolyte due to passage of electric current and splits the electrolyte into its ions. The electrolysis is used in many areas which are given below: 1) Electroplating-It is the coating of metal over another metal using electric current. 2) Electro refining-It is used to purify an impure metal using electrolysis. 3) Production of metals and non-metals-Many metals and non-metals, such as chlorine, aluminium, and magnesium are also produced using electrolysis.