MAGNESiUM (Mg)

A typical metal with atomic number 12.
Period: 3
Group: IIA
Atomic weight: 24
Protons: 12
Neutrons: 12 (frequent isotope Mg-24)
Electrons: 12 or 10 if constant oxidation degree is +2
Electron configuration: 2, 8, 2
(+12) ) ) )
      2 8 2 (Free metal)

(+12) ) )
      2 8 (Cation)
Electron formula:
1s2 2s2 2p6 3s2
Electronegativity: 1.2

Gray metal
Melting point 650*С
Boiling point 1105*С
Hexagonic crystall lattice
Clark 19 kg/tonn
Sea water 0,13 %

Well-Known Substances:
Carnallite MgCl₂ • KCl • 6H₂O
Bishofite MgCl₂ • 6H₂O
Kieserite MgSO₄ • H₂O
Epsomite MgSO₄ • 7H₂O
Kainite KCl • MgSO₄ • 3H₂O
Magnesite MgCO3
Dolomite CaCO3 x MgCO3
Brucite Mg(OH)2

Mg production: USA 43%; CIS 26%; Norway 17%

<sub>Reactive metal covered by MgO

Typical reactions:</sub>

Magnesium preparation:
MgCl2 => (electrolysis) Mg + Cl2
MgO + C => Mg + CO

2MgO + CaO + Si = CaSiO₃ + 2Mg

CaCO₃·MgCO₃ = CaO + MgO + 2CO<sub>2

Mg + 2H2O => Mg(OH)2 + H2

Mg + 2HCl => MgCl2 + H2

2Mg + O2 => 2MgO

3Mg + N2 => Mg3N2

2Mg + CO2 => 2MgO + C

Significance:</sub>

MgH2 - capacious accumulator of hydrogen
MgO - refractory material
Mg(ClO4)2 (anhydrone) - profound reclamation of gases in labs
MgF2 - used in optics as synthetic monocrystalls
MgBr2 - used as electrolyte for chemical backup power source
Also Mg is used in medicine, warfare, photographing, accumulators