All chemical elements

Symbol

La

Atomic number

57

Chemical property

Lan­thanide

Origin o the name

the Greek lanthanein, 'to lie hidden'

Group

3

Period

6

Atomic weight (u)

138.90547

Atomic weight uncertainty (u)

0.00007

Density (g/cm³)

6.145

Melting point (K)

1193

Boiling point (K)

3737

Heat capacity (J/(g·K))

0.195

Electro-negativity

1.1

Abundance in earth's crust (mg/kg)

39