12Mg
Element 12
Magnesium
Alkaline earth
Magnesium is a chemical element with symbol Mg and atomic number 12.
Key data
- Atomic number
- 12
- Atomic mass
- 24.305 u
- Group / Period
- 2 / 3
- Block
- s-block
- Phase at STP
- Solid
- Density
- 1.738 g/cm³
- Melting point
- 649.9 °C
- Boiling point
- 1089.8 °C
- Electron configuration
- [Ne] 3s2
Common uses
- •Lightweight alloys
- •Camera flashes
- •Chlorophyll
Discovery
Year: 1755
Discovered by: Joseph Black
Frequently asked questions
What is the atomic number of Magnesium?
Magnesium has atomic number 12. Its symbol is Mg and its atomic mass is 24.305 u.
What category of element is Magnesium?
Magnesium is classified as alkaline earth. It sits in group 2, period 3 of the periodic table.
What is Magnesium used for?
Common uses of Magnesium include: Lightweight alloys, Camera flashes, Chlorophyll.
When was Magnesium discovered?
Magnesium was discovered in 1755 by Joseph Black.
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