Page 16 - Curriculum Visions Dynamic Book

S see Sulphur
Samarium (Sm)
Element 62. A hard, brittle, silvery- white metal belonging to the rare- earth metals (lanthanides) in the Periodic Table. It does not oxidise quickly and keeps its bright metallic lustre well. It catches fire at 150°C. Samarium salts are pale yellow.
Discovery
Samarium was discovered in France
in 1853 by Jean-Charles Galinard de Marignac, using a spectrometer (an instrument that detects the type of light given off when a sample of the element is heated). It was isolated from other rare earths in France in 1879 by Paul-Émile Lecoq de Boisbaudran.
Technology
It is used with cobalt to make permanent magnets.This alloy has the highest resistance to demagnetisation of any known material. It also absorbs infra-
red light, makes lasers, and is a catalyst for speeding up reactions. It is also used in the movie industry for carbon-arc lighting. Samarium oxide is used in the control rods of some nuclear reactors.
Geology
It is not found as a native element.
It is the 40th most abundant
element on the Earth’s surface. It appears with other rare-earth elements, but typically in the minerals cerite, gadolinite, monazite and bastanite.
Biology
Samarium is not found in living things.
Key facts...
Name: samarium
Symbol: Sm
Atomic number: 62
Atomic weight: 150.36
Position in Periodic Table: inner transition
metal; period 6 (lanthanide series) State at room temperature: solid Colour: silvery-white
Density of solid: 7.52 g/cc
Melting point: 1,074°C
Boiling point: 1,794°C
Origin of name: named after the mineral
samarskite in which the element is found. The mineral was, in turn, named after a Russian mine official, Colonel Samarski.
Shell pattern of electrons: 2–8–18–24–8–2
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