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Science

Electrolysis

Electrolysis is the process by which ionic substances are broken down into simpler substances using electricity. During electrolysis, metals and gases may form at the electrodes.

What is electrolysis?

Ionic substancesionic substance: Ionic substances form when a metal reacts with a non-metal. They contain charged particles called ions. contain charged particlescharged particle: A particle that carries an electric charge. called ions [ion: Positively- or negatively-charged particles - eg positively charged hydrogen, sodium and potassium atoms. Ion charge helps determine a substance's acidity or alkalinity ]. For example, lead bromide contains positively charged lead ions and negatively charged bromide ions.

Electrolysis is the process by which ionic substances are decomposed (broken down) into simpler substances when an electric current is passed through them.

For electrolysis to work, the ions must be free to move. Ions are free to move when an ionic substance is dissolved in water or when melted. For example, if electricity is passed through moltenmolten: Molten means reduced to liquid form by heating. It is mainly used to describe rock, glass or metal. lead bromide, the lead bromide is broken down to form lead and bromine.

What happens in electrolysis. Positively charged ions move to the negatively charged electrode; negatively charged ions move to the positive electrode

Electrolysis

Here is what happens during electrolysis:

  • Positively charged ions move to the negative electrodeelectrode: Electrodes are conductors used to establish electrical contact with a circuit. The electrode attached to the negative terminal of a battery is called a negative electrode, or cathode. The electrode attached to the positive terminal of a battery is the positive electrode, or anode. during electrolysis. They receive electrons [electron: An electron is a very small negatively-charged particle found in an atom in the space surrounding the nucleus. ] and are reducedreduction: Reduction is a reaction in which oxygen is removed from a substance. Reduction also means a gain in electrons..
  • Negatively charged ions move to the positive electrode during electrolysis. They lose electrons and are oxidisedoxidation: Oxidation is a reaction in which oxygen combines with a substance. Oxidation also means a loss of electrons..

The substance that is broken down is called the electrolyteelectrolyte: An electrolyte is a substance which in solution will conduct an electric current..

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