Magnesium (Mg)
Silvery metallic element belonging to group 2 of the periodic table (alkaline-earth metals). It is essential for living organisms, and is used in a number of light alloys. Chemically very reactive, it forms a protective oxide coating when exposed to air and burns with an intense white flame. It also reacts with sulphur, nitrogen and the halogens. First isolated by Bussy in 1828.
| Atomic Number | 12 |
|---|---|
| Atomic Weight | 24.305 |
| Mass Number | 24 |
| Group | 2 |
|---|---|
| Period | 3 |
| Block | s |
| Protons | 12 p+ |
|---|---|
| Neutrons | 12 n0 |
| Electrons | 12 e- |
Properties
| Atomic Radius | 150 pm
|
|---|---|
| Atomic Volume | 14 cm³/mol
|
| Covalent Radius | 139 pm
|
| Metallic Radius | 136 pm
|
| Ionic Radius | 57 pm
|
| Crystal Radius | 71 pm
|
| Van der Waals radius |
173 pm
|
| Density | 1.74 g/cm³
|
| Boiling Point | 1,363 K
|
| Melting Point | 922 K
|
| Electrons per shell | 2, 8, 2 |
| Electronegativity |
1.31
|
| Electrophilicity | |
| Proton Affinity | 819.6 kJ/mol
|
| Electron Affinity | |
| Ionization Potential | 7.646235 eV/particle
|
| Heat of Vaporization | 131.8 kJ/mol
|
| Heat of Fusion | 9.2 kJ/mol
|
| Heat of Formation | 147.1 kJ/mol
|
| Molar Heat Capacity | 24.869 J/(mol K)
|
| Specific Heat Capacity | 1.023 J/(g⋅K)
|
| Thermal Conductivity | 156 W/(m K)
|
| Gas Basicity | 797.3 kJ/mol
|
| Dipole Polarizability | 71.2 a₀
|
| C6 Dispersion Coefficient | 626 a₀
|
| Oxidation States | 1, 2 |
| Color | Silver
|
| Crystal Structure | Simple Hexagonal (HEX) |
| Lattice Constant | 3.21 Å
|
| Bulk Modulus | |
| Electrical Resistivity | |
| Electron Configuration | [Ne] 3s2 |
| Magnetic Ordering | |
| Magnetic Susceptibility | |
| Phase | Solid |
| Poisson Ratio | |
| Shear Modulus | |
| Young's Modulus | |
| Allotropes | |
| Alternate Names | |
| Adiabatic Index | |
| Appearance | |
| Electric Conductivity | |
| Critical Pressure | |
| Critical Temperature | |
| Curie Point | |
| Electrical | |
| Hardness | |
| Magnetic Susceptibility | |
| Magnetic | |
| Neel Point | |
| Neutron Cross Section | |
| Neutron Mass Absorption | |
| Gas Phase | |
| Quantum Numbers | |
| Refractive Index | |
| Space Group | |
| Speed of Sound | |
| Superconducting Point | |
| Thermal Expansion | |
| Valence Electrons | |
| Classification | |
| Category | Alkaline earth metals, Alkaline earth metals |
| CAS Group | IIA |
| IUPAC Group | IIA |
| Glawe Number | 73 |
| Mendeleev Number | 76 |
| Pettifor Number | 73 |
| Geochemical Class | major |
| Goldschmidt Class | litophile |
| Radioactivity | |
| Radioactive | No |
| Decay Mode | |
| Half-Life | |
| Lifetime | |
| Abundance | |
| Abundance in Earth's crust | 23,300 mg/kg
|
| Abundance in Oceans | 1,290 mg/L
|
| Abundance in Human Body | |
| Abundance in Meteor | |
| Abundance in Sun | |
| Abundance in Universe | 0.06% |
Isotopes of Magnesium
Stable Isotopes
24Mg 25Mg 26Mg
Unstable Isotopes
19Mg 20Mg 21Mg 22Mg 23Mg 27Mg 28Mg 29Mg 30Mg 31Mg 32Mg 33Mg 34Mg 35Mg 36Mg 37Mg 38Mg 39Mg 40Mg
History
Scottish chemist Joseph Black recognized magnesium as an element in 1755. Magnesium was first isolated by Sir Humphry Davy in 1808, in London. He used electrolysis on a mixture of magnesia and mercuric oxide. Antoine Bussy prepared it in coherent form in 1831. From Magnesia, district in Thessaly
| Discoverers | Sir Humphrey Davy |
|---|---|
| Discovery Location | England |
| Discovery Year | 1808 |
| Name Origin | From Magnesia ancient city in district of Thessaly, Greece. |
Because serious fires can occur, great care should be taken in handling magnesium metal
When it burns in air, magnesium produces a brilliant white light
Uses
Magnesium is widely used in the manufacturing of mobile phones, laptop computers, cameras, and other electronic components. The brilliant light it produces when ignited is made use of in photography, flares, pyrotechnics and incendiary bombs. Magnesium compounds such as the hydroxide (milk of magnesia), sulfate (Epsom salts), chloride and citrate are used for medicinal purposes. Used in alloys to make airplanes, missiles and other uses for light metals. Has structural properties similar to aluminium. But since it is flammable at temperatures of burning gasoline, its uses are limited.
Sources
Usually obtained by electrolysis of melted magnesium chloride (MgCl2) found in sea water. Each cubic mile of seawater contains about 12 billion pounds of magnesium.