Electrolysis of molten ionic compounds
This is what happens during electrolysisThe decomposition (breakdown) of a compound using an electric current..
- Positively-charged ions move to the negative electrodeA conductor 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. (cathodeThe negative electrode during electrolysis.). They receive electrons and are reductionThe loss of oxygen, gain of electrons, or gain of hydrogen by a substance during a chemical reaction..
- Negatively-charged ions move to the positive electrode (anodeThe positive electrode during electrolysis.). They lose electrons and are oxidationThe gain of oxygen, or loss of electrons, by a substance during a chemical reaction..
- The substance that is broken down is called the electrolyteA substance which, when molten or in solution, will conduct an electric current..
Ionic substances contain charged particleA particle, usually an ion or electron, that carries an electrical charge. called ionElectrically charged particle, formed when an atom or molecule gains or loses an electron/electrons.. For example, lead(II) bromide (PbBr2) contains positively charged lead ions (Pb2+) and negatively charged bromide ions (Br鈥).
Electrolysis is the process by which ionic substances are decomposed (broken down) into simpler substances when an electric current is passed through them.
Electricity is the flow of electronSubatomic particle, with a negative charge and a negligible mass relative to protons and neutrons. or ions. For electrolysis to work, the compoundA substance formed by the chemical union of two or more elements. must contain ions. covalentA covalent substance is a molecule containing one or more covalent bonds (shared pairs of electrons). compounds cannot act as electrolytes because they contain neutral atomAll elements are made of atoms. An atom consists of a nucleus containing protons and neutrons, surrounded by electrons..
The ions must be free to move, which is possible when an ionic substance is dissolveWhen something is broken up in a liquid and no longer exists. in water or it is melted. For example, if electricity is passed through moltenA term used to describe a liquid substance (eg rock, glass or metal) formed by heating a solid. lead(II) bromide, the lead(II) bromide is broken down to form lead and bromine.