Dec 17 2012
Samarium was first observed spectroscopically by a Swiss chemist, Jean Charles Galissard de Marignac in 1853 while working with dydimia. Paul-Émile Lecoq de Boisbaudran, a French chemist first isolated samarium along with didymium from the mineral samarskite in 1879. The element derived its name from the mineral samarskite from which it was isolated.
Basic Information
| Name |
Samarium |
| Symbol |
Sm |
| Atomic number |
62 |
| Atomic weight |
150.36 amu |
| Standard state |
Solid at 298 K |
| CAS Registry ID |
7440-19-9 |
| Group name |
Lanthanoid |
| Period in periodic table |
6 |
| Block in periodic table |
f-block |
| Color |
Silvery white |
| Classification |
Metallic |
| Melting point |
1347 K (1074°C or 1965°F) |
| Boiling point |
2067 K (1794°C or 3261°F) |
| Density |
7.52 g/cm3 |
| Phase at room temperature |
Solid |
Occurrence
Samarium is present in rare earth ores including samarskite, bastnaesite and monazite.
Samarium - Periodic Table of Videos
Isotopes
It has 30 isotopes with mass numbers ranging from 131Sm to 160Sm. It consists of seven naturally-occurring isotopes that include 144Sm, 147Sm, 148Sm, 149Sm, 150Sm, 152Sm and 154Sm.
Production
Pure samarium can be produced by electrolyzing the molten chloride with sodium chloride. In addition, it can be commercially recovered from bastnaesite and monazite sand with the help of ion exchange and solvent extraction techniques.
Key Properties
The following are the key properties of samarium:
- It is a bright, hard silvery metal
- It exists in its trivalent state
- It is stable in air at normal temperatures
- It forms oxide with moist air
- It is the hardest and most brittle rare earth element.
Applications
The applications of samarium include the following:
- It is used as a catalyst for dehydrogenating and dehydrating ethanol
- 153Sm is used to treat cancer owing to its radioactivity
- It is mainly used in preparing samarium-cobalt alloy magnets for electric guitars, small motors and headphones
- It is used as an absorber in nuclear reactors
- Its oxide is used for manufacturing special infrared adsorbing glass for carbon arc-lamp electrodes
- It is useful in doping calcium fluoride crystals employed in optical lasers.
Sources and Further Reading