Magnesium
Jump to navigation
Jump to search
Chemical formula | {{#Chem:Mg}} |
---|---|
Atomic Number | 12 |
OTP appearance | silver grey solid |
Molar Mass(g/mol) | 24.3 |
Density(g/cc) | 1.8 |
Melting Point(°C) | 650 |
Boiling Point(°C) | 1091 |
NFPA 704 |
Uses
Justification Questioned
Other
- structural material
- high temperature deflagration
- Key component of Grignard reactions.
Natural occurence
- Elemental magnesium does not occur naturally
- magnesium carbonate occurs as the mineral magnesite
- magnesium hydroxide occurs as the mineral brucite
- magnesium sulfate occurs as the mineral epsomite
Production
Extraction
from magnesium chloride
A patent[1] covers this process
- Produce a saturated solution of magnesium chloride
- Add liquid mercury
- Run 4-5V through the solution and mercury, amalgamating the magnesium and freeing the chlorine.
- N.B. Good operating percentage is 2-4%Mg (w/w) in HgMg amalgam, which is 15-30% (molar)
- {{#Chem: MgCl2(aq) + Hg(l) { = 4-5V, 80°C } HgMg(l) + Cl2(g) }}
- Flow the mercury out of the tube and cool it, producing a solid and liquid phase
- {{#Chem: HgMg amalgam { = 0°C } Hg5Mg2(s) + Hg(l) }}
- Recycle the liquid mercury into the cell
- Heat the solid, boiling the mercury and melting the magnesium
- {{#Chem: Hg5Mg2 { = ≥ 650°C } 5Hg(v) + 2Mg(l) }}
- Condense the vaporous mercury and recycle
- Accumulate liquid magnesium until you have enough
- Solidify magnesium
Purification
The most common adulterant is calcium. Magnesium oxalate is soluble in water and calcium oxalate is not.
Testing
Storage
Disposal
See Also
References
- ↑ US patent 3074861
Link courtesy Google