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MAGNESIUM

Magnesium is a silvery reactive element belonging to the group II of the periodic table. It is characterised by

 

1. Atomic number 12

 

2. Relative atomic mass 24.321

 

3. Relative density 1.74

 

4. Melting point 651^OC

 

5. Boiling point 1107^OC

OCCURRENCE

Magnesium basically occurs in minerals, as magnesite(MgCO₃), dolomite(MgCl₂.KCl.6H₂O) and dolomite (MgCO₃.CaCO₃).

EXTRACTION

Magnesium is prepared by the electrolysis of fused magnesium chloride

MgCl₂ è Mg²⁺ + 2Cl^-

At anode

2Cl- è Cl2 + 2e

At cathode

Mg²⁺ + 2e è Mg

CHEMICAL PROPERTIES

 

1. Reducing Action

B₂O₃ + 3Mg è 2B + 3MgO

3CO₂ + 4Mg è C + 2Mg₂CO₃

2. Action of air

H2O

2CO2

 

2Mg + O₂ è 2MgO

3Mg + N₂ è 2Mg₃N₂

3. Action of Water

Mg + H₂O(steam) è MgO + H₂

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