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57La

Element 57

Lanthanum

Lanthanides

Lanthanum is a soft, ductile, silvery-white metallic chemical element with symbol La and atomic number 57.

Key data

Atomic number
57
Atomic mass
138.905 u
Group / Period
3 / 6
Block
f-block
Phase at STP
Solid
Density
6.162 g/cm³
Melting point
919.9 °C
Boiling point
3463.8 °C
Electron configuration
[Xe] 5d16s2

Common uses

  • Camera lenses
  • Hybrid car batteries
  • Lighter flints

Discovery

Year: 1839

Discovered by: Carl Gustaf Mosander

Frequently asked questions

What is the atomic number of Lanthanum?

Lanthanum has atomic number 57. Its symbol is La and its atomic mass is 138.905 u.

What category of element is Lanthanum?

Lanthanum is classified as lanthanides. It sits in group 3, period 6 of the periodic table.

What is Lanthanum used for?

Common uses of Lanthanum include: Camera lenses, Hybrid car batteries, Lighter flints.

When was Lanthanum discovered?

Lanthanum was discovered in 1839 by Carl Gustaf Mosander.

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