View source for Extracting Metals by Electrolysis

==Key Stage 3==
===Meaning===
'''Electrolysis''' is a way to [[Extraction of Metals|extract metals]] from [[mineral]]s when the [[metal]] is more [[Reactivity Series|reactive]] than [[Carbon]].

===About Extracting Metals by Electrolysis===
: [[Metal]]s that are more [[Reactivity Series|reactive]] than [[Carbon]] cannot be [[Displacement Reaction|displaced]] with [[Carbon]] so [[electrolysis]] is used to [[Extraction of Metals|extract]] them.
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|[[File:ElectrolysisCell.png|center|500px]]
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| style="height:20px; width:200px; text-align:center;" |[[Carbon]] [[electrode]]s are used to pass an [[Electrical Current]] through the [[molten]] [[mineral]]. The [[metal]] collects at the [[cathode]] which carries a negative [[Electrical Charge|charge]] and the [[pure]] [[metal]] is removed from the '''electrolysis''' cell.
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==Key Stage 4==
===Meaning===
'''Extraction of metals by electrolysis''' is a method of obtaining a [[metal]] from a [[mineral]].

===About Extracting Metals by Electrolysis===
: '''[[Electrolysis]]''' is usually used to [[Extraction of Metals|'''extract metals''']] when the [[metal]] is more [[Reactivity Series|reactive]] than [[Carbon]] or the [[mineral]] is [[soluble]] in [[water]] making it cheaper to '''extract by electrolysis''' than by [[smelting]].
There are two possible methods used to '''extract metals by electrolysis''':
*Electrolysis of the Mineral in Solution - Used when the [[mineral]] is [[soluble]] in [[water]] and the [[metal]] does not [[Chemical Reaction|react]] with [[water]].
*Electrolysis of the Molten Mineral - Used when the [[mineral]] is [[insoluble]] in [[water]] or the [[metal]] [[Chemical Reaction|reacts]] strongly with [[water]].
: [[Aluminium]] is a special case in which the [[mineral]] is not [[dissolve]]d in [[water]] but in a [[solvent]] called Cryolite at very high [[temperature]]s. This is done because the [[mineral]] [[melt]]s at an even higher [[temperature]] than the cryolite so it is easier to [[dissolve]] it in the cryolite than to heat the [[mineral]] beyond its [[Melting Point|melting point]].

===Electrolysis of Molten Minerals===
Used when the [[mineral]] is [[insoluble]] in [[water]] or the [[metal]] [[Chemical Reaction|reacts]] strongly with [[water]].
: The [[electrolysis]] of [[molten]] [[Ionic Compound|ionic compounds]] [[Decompose (Chemistry)|decompose]]s those [[Ionic Compound|ionic compounds]] in a [[liquid]] [[State of Matter|state]].
: The [[Ionic Compound|ionic compound]] must be [[heated]] and [[melting|melted]] before [[electrolysis]].
: [[Non-metal]] [[ion]]ic [[element]]s or [[compound]]s will be collected at the [[anode]] where they lose their extra [[electron]]s.
: [[Metal]] [[ion]]s will be collected at the [[cathode]] where they gain [[electron]]s.

===Electrolysis of Aqueous Minerals===
Used when the [[mineral]] is [[soluble]] in [[water]] and the [[metal]] does not [[Chemical Reaction|react]] with [[water]].
: The [[electrolysis]] of [[aqueous]] [[Ionic Compound|ionic compounds]] [[Decompose (Chemistry)|decompose]]s those [[Ionic Compound|ionic compounds]] in [[solution]].
: [[Non-metal]] [[ion]]ic [[element]]s or [[compound]]s will be collected at the [[anode]] where they lose their extra [[electron]]s.
: [[Metal]] [[ion]]s less [[Reactivity|reactive]] than [[Hydrogen]] will be collected at the [[cathode]] where they gain [[electron]]s.