Lanthanum
| Symbol | La |
| Atomic Number | 57 |
| Atomic Mass | 198.905 g.mol -1 |
| Discovered by | Carl Gustav Mosander in 1839 |
| Group | Lanthanides | Melting point | 920°C, 1688°F, 1193 K |
| Period | 6 | Boiling point | 3464°C, 6267°F, 3737 K |
| Block | d | Density (g cm−3) | 6.15 |
| Atomic number | 57 | Relative atomic mass | 138.905 |
| State at 20°C | Solid | Key isotopes | 139La |
| Electron configuration | [Xe]5d1 6s2 | CAS number | 7439-91-0 |
| ChemSpider ID | 22369 | ChemSpider is a free chemical structure database. | |
- Lanthanum is a chemical element with an atomic number of 57 and represented by the symbol La in the Periodic Table.
- The chemical Lanthanum is found in modern television sets, the energy saving lamps, fluorescent tubes, etc.
- It is used in the field of optics as lenses and radiation absorbing glasses.
- It is known to increase the resistivity and malleability of steel.
- It is also used for catalysis in the field of petroleum refineries.
- It is used in the production of catalyst and also in polishing of glass.
- It is found abundantly in the environment.
- It appears like a white- silvery metal.
- This metal is soft in nature and also active and ductile.
- On reaction with water, this metal oxidizes forming its hydroxide.
- The salts of Lanthanum are insoluble in water.
- About 12.000 tonnes of lanthanum is produced worldwide every year.
- The main problem with this element is its disposal. By the industrial wastes getting dumped into the water bodies mainly the petroleum producing industry.
- It produces severe damage to plants and animals and also causes nervous system disorder in humans.
Practise This Question
