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Science

Electrolysis

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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.

Electrolysis

To understand electrolysis, you need to know what an ionic substance is.

Ionic substances form when a metal reacts with a non-metal. They contain charged particles called ions [ions: Electrically charged particles, formed when an atom or molecule gains or loses electrons. ]. For example, sodium chloride forms when sodium reacts with chlorine. It contains positively charged sodium ions and negatively charged chloride ions. Ionic substances can be broken down by electricity.

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 moltenmolten: Molten means reduced to liquid form by heating. It is mainly used to describe rock, glass or metal. (melted). For example, if electricity is passed through copper chloride solution, the copper chloride is broken down to form copper metal and chlorine gas.

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 electrode during electrolysis. They receive electrons 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..

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