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The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
For alloys containing transition metal elements there is a difficulty in interpretation of the Hume-Rothery electron concentration rule, as the values of e/a values (number of itinerant electrons per atom) for transition metals have been quite controversial for a long time, and no satisfactory solutions have yet emerged. [9] [10]
Notes [ edit ] ^ Hardness can vary by several hundred percent depending on the pretreatment, see e.g. Iron#Mechanical properties and Angelo Basile; Fausto Gallucci (2011).
This line has been called the amphoteric line, [2] the metal-nonmetal line, [3] the metalloid line, [4] [5] the semimetal line, [6] or the staircase. [2] [n 1] While it has also been called the Zintl border [8] or the Zintl line [9] [10] these terms instead refer to a vertical line sometimes drawn between groups 13 and 14.
As a metalloid, its chemistry is largely covalent in nature, noting it can form brittle alloys with metals, and has an extensive organometallic chemistry. Most alloys of arsenic with metals lack metallic or semimetallic conductivity. The common oxide of arsenic (As 2 O 3) is acidic but weakly amphoteric. Antimony, showing its brilliant lustre
Metals in relatively high oxidation states tend to form covalent structures (e.g. WF 6, OsO 4, TiCl 4, AlCl 3), as do the more noble metals even in low oxidation states (e.g. AuCl, HgCl 2). There are also some metal oxides displaying electrical (metallic) conductivity, like RuO 2, ReO 3, and IrO 2. [4]
The definition of metal includes: Post-transition metals, i.e. aluminium, gallium, indium, thallium, tin, lead, and bismuth. Metalloids, e.g. silicon, germanium, arsenic, antimony and tellurium. Homogeneous and heterogeneous solid solutions of metals, and interstitial compounds such as carbides and nitrides are excluded under this definition ...
Iron has five nitrides observed at ambient conditions, Fe 2 N, Fe 3 N 4, Fe 4 N, Fe 7 N 3 and Fe 16 N 2.They are crystalline, metallic solids. Group 7 and group 8 transition metals form nitrides that decompose at relatively low temperatures—iron nitride, Fe 2 N decomposes with loss of molecular nitrogen at around 400 °C and formation of lower-nitrogen content iron nitrides.