| Tecken | Mg |
| Atomnummer | 12 |
| Grupp | 2 (Alkaliska jordartsmetaller) |
| Period | 3 |
| Block | s |
| Ämnesklass | Alkalisk jordartsmetall |
| Utseende | Shiny grey solid |
| Färg | Silver |
| Antal protoner | 12 p+ |
| Antal neutroner | 12 n0 |
| Antal elektroner | 12 e- |
| Fas vid STP | Fast |
| Densitet | 1.738 g/cm3 |
| Relativ atommassa | 24.304 u |
| Smältpunkt | 923 K 649.85 °C 1201.73 °F |
| Kokpunkt | 1363 K 1089.85 °C 1993.73 °F |
| Ångbildningsvärme | 127.6 kJ/mol |
| Elektronegativitet (Paulingskalan) | 1.31 |
| Elektronaffinitet | -40 kJ/mol |
| Oxidationstal | +1, +2 (a strongly basic oxide) |
| Jonisationspotential |
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| Upptäckt | Joseph Black (1755) |
| Första isolation | Humphry Davy (1808) |
Upptäckten av magnesium The name magnesium originates from the Greek word for locations related to the tribe of the Magnetes, either a district in Thessaly called Magnesia or Magnesia ad Sipylum, now in Turkey. The metal was first isolated by Sir Humphry Davy in England in 1808. He used electrolysis on a mixture of magnesia and mercuric oxide. Antoine Bussy prepared it in coherent form in 1831. Davy's first suggestion for a name was magnium, but the name magnesium is now used in English and all major European languages but Russian. | |