Mg
Magnesium
Element 12 · 24.305 u
Magnesium is a lightweight alkaline earth metal essential for hundreds of biochemical reactions.
Physical Properties
| Atomic Mass | 24.305 u |
| Density | 1.738 g/cm³ |
| Melting Point | 923.0 K |
| Boiling Point | 1363.0 K |
| Appearance | Shiny gray metallic |
| State at Room Temp | Solid |
Chemical Properties
| Electronegativity | 1.31 (Pauling) |
| 1st Ionization Energy | 737.7 kJ/mol |
| Electron Affinity | -40.0 kJ/mol |
| Oxidation States | +1, +2 |
Atomic Properties
| Electron Configuration | [Ne] 3s2 |
| Atomic Radius | 160.0 pm |
| Covalent Radius | 141.0 pm |
| Van der Waals Radius | 173.0 pm |
Discovery
| Discovered By | Joseph Black |
| Discovery Year | 1755 |
| Location | Edinburgh, Scotland |
| Named After | Magnesia, a district in Thessaly, Greece |
About Magnesium
Magnesium is a shiny gray solid that is strong yet light. It is the eighth most abundant element in Earth's crust. Magnesium is essential for all living cells as a cofactor in ATP-related enzymes. It burns with a brilliant white flame.
Uses & Applications
Lightweight alloys for aircraft and cars, fireworks and flares, antacids, Epsom salts, and chlorophyll in plants.
Fun Fact
Magnesium burns so brightly it was used as photographic flash powder, and its fire cannot be put out with water.
Isotopes
| Mass Number | Abundance | Half-Life | Stable |
| 24 | 0.7899% | - | Yes |
| 25 | 0.1% | - | Yes |
| 26 | 0.1101% | - | Yes |
Electron Configuration
[Ne] 3s2