In chemistry, the term transition metal (sometimes also called a transition element) has two possible meanings:
- The IUPAC definition states that a transition metal is "an element whose atom has an incomplete d sub-shell, or which can give rise to cations with an incomplete d sub-shell".
- Most scientists describe a "transition metal" as any element in the d-block of the periodic table, which includes groups 3 to 12 on the periodic table. All elements in the d-block are metals. In actual practice, the f-block is also included in the form of the lanthanide and actinide series.
Jensen has reviewed the history of the terms transition element (or metal) and d-block. The word transition was first used to describe the elements now known as the d-block by the English chemist Charles Bury in 1921, who referred to a transition series of elements during the change of an inner layer of electrons (for example n=3 in the 4th row of the periodic table) from a stable group of 8 to one of 18, or from 18 to 32.
Read more about Transition Metal: Classification, Characteristic Properties
Famous quotes containing the words transition and/or metal:
“The god or hero of the sculptor is always represented in a transition from that which is representable to the senses, to that which is not.”
—Ralph Waldo Emerson (1803–1882)
“We are supposed to be the children of Seth; but Seth is too much of an effete nonentity to deserve ancestral regard. No, we are the sons of Cain, and with violence can be associated the attacks on sound, stone, wood and metal that produced civilisation.”
—Anthony Burgess (b. 1917)