Page 48 - Curriculum Visions Dynamic Book

Dysprosium (Dy)
Element 66.A rare-earth element (lanthanide) in the Periodic Table. It is a bright, shiny, silvery-looking and very reactive metal with a high melting point. Dysprosium is stable in air at room temperature and is soft enough to be cut with a knife. It does not tarnish readily. Dysprosium salts are yellow or yellow–green.All of the salts are very magnetic.
Discovery
It was discovered in 1886 in France by Paul-Émile Lecoq de Boisbaudran, but it was only isolated in the 1950s.
Technology
It readily absorbs neutrons, and in the form of dysprosium oxide it is used in control rods for nuclear reactors. It also goes into an alloy for specialised stainless steels and to make laser materials.
Geology
It does not occur as a native element. It is found in small quantities in minerals such as gadolinite, xenotime, monazite and bastanite.The most important ores are monaziate and bastnasite. Dysprosium
is produced by reducing dysprosium trifluoride using calcium.
Biology
Dysprosium is not found in living things and is not encountered except in specialised laboratories.
Key facts...
Name: dysprosium
Symbol: Dy
Atomic number: 66
Atomic weight: 162.5
Position in Periodic Table: inner transition metal;
period 6 (lanthanide series)
State at room temperature: solid
Colour: silvery-white
Density of solid: 8.55 g/cc
Melting point: 1,412°C
Boiling point: 2,567°C
Origin of name: from the Greek word dysprositos,
meaning hard to obtain
Shell pattern of electrons: 2–8–18–28–8–2
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