this is about the extraction of metals by electrolysis and the products etc..

the electrolysis of :

lead bromide

sodium chloride

potassium chloride

magnesium chloride

zinc chloride

aluminum

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Extraction of Metals
Electrolysis General Description.
The elements in ionic compounds can be separated by electrolysis.
Metals above carbon in the reactivity series (potassium, sodium, lithium, calcium,
magnesium and aluminium) are extracted by electrolysis.
Extraction from the metal ore involves reduction of the metal, and electrons can
reduce any metal…

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LEAD BROMIDE (electrolysis)

Electrolysis of Lead Bromide:
Lead bromide must be heated until it is molten before it will conduct electricity.
Electrolysis separates the molten ionic compound into its elements.






The reactions at each electrode are called half equations.
The half equations are written so that the same number of…

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The reactions at each electrode are called half equations.
The half equations are written so that the same number of electrons occur in
each equation.

2Na+ + 2e 2Na (sodium metal at the ()cathode).
2Cl 2e Cl2 (chlorine gas at the (+)anode).
Sodium ions gain electrons (reduction) to form sodium…

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The reactions at each electrode are called half equations.
The half equations are written so that the same number of electrons occur in each
equation.

2K+ + 2e 2K (potassium metal at the ()cathode).
2Cl 2e Cl2 (chlorine gas at the (+)anode).
Potassium ions gain electrons (reduction) to form potassium…

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Mg2+ + 2e Mg (magnesium metal at the ()cathode).
2Cl 2e Cl2 (chlorine gas at the (+)anode).
Magnesium ions gain electrons (reduction) to form magnesium atoms.
Chloride ions lose electrons (oxidation) to form chlorine atoms.
The chlorine atoms combine to form molecules of chlorine gas.

The overall reaction is: MgCl2(l)…

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Zn2+ + 2e Zn (zinc metal at the ()cathode).
2Cl 2e Cl2 (chlorine gas at the (+)anode).
Zinc ions gain electrons (reduction) to form zinc atoms.
Chloride ions lose electrons (oxidation) to form chlorine atoms.
The chlorine atoms combine to form molecules of chlorine gas.

The overall reaction is :…

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In the middle of the nineteenth century it was found that alumina dissolved in cryolite.

Cryolite is sodium aluminium fluoride Na3AlF6.
A solution of alumina in cryolite melts at about 900 °C and electrolysis is done at
about 950 °C.

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