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A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
The elements, after purification from other rare-earth metals, are isolated as oxides; the oxides are converted to fluorides during reactions with hydrofluoric acid. [79] The resulting fluorides are reduced with alkaline earth metals or alloys of the metals; metallic calcium is used most frequently. [79] For example: Sc 2 O 3 + 3 HF → 2 ScF 3 ...
The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows ("periods") and columns ("groups"). It is an icon of chemistry and is widely used in physics and other sciences.
A heavy metal is any relatively dense metal, either single element or multielement. [46] Magnesium , aluminium and titanium alloys are light metals of significant commercial importance. [ 47 ] Their densities of 1.7, 2.7 and 4.5 g/cm 3 range from 19 to 56% of the densities of other structural metals, [ 48 ] such as iron (7.9) and copper (8.9 ...
Transactinide elements – Elements after the actinides (atomic number greater than 103). Transplutonium elements – Elements with atomic number greater than 94. Transuranium elements – Elements with atomic number greater than 92. Valve metal - a metal which, in an electrolytic cell, passes current in only one direction.
Beryllium copper (0.5-3% beryllium, 99.5%-97% copper) [4] Billon ; Brass see also Brass §Brass types for longer list. Calamine brass ; Chinese silver ; Dutch metal ; Gilding metal ; Muntz metal ; Pinchbeck ; Prince's metal ; Tombac ; Bronze (tin, aluminum or other element) Aluminium bronze
In chemistry, a transition metal (or transition element) is a chemical element in the d-block of the periodic table (groups 3 to 12), though the elements of group 12 (and less often group 3) are sometimes excluded.
Naturally occurring platinum and platinum-rich alloys were known by pre-Columbian Americans for many years. [5] However, even though the metal was used by pre-Columbian peoples, the first European reference to platinum appears in 1557 in the writings of the Italian humanist Julius Caesar Scaliger (1484–1558) as a description of a mysterious metal found in Central American mines between ...