Magnesium is a chemical element with symbol Mg and atomic number 12. It is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column of the periodic .
Symbol: Mg
Atomic mass: 24.305 u ± 0.0006 u
Electron configuration: [Ne] 3s2
Atomic number: 12
Melting point: 1,202°F (650°C)
Discovered: 1755
Discoverer: Joseph Black