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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.
A metal (from Ancient Greek μέταλλον (métallon) 'mine, quarry, metal') is a material that, when polished or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. These properties are all associated with having electrons available at the Fermi level, as against nonmetallic materials which do not. [1]:
A material property is an intensive property of a material, i.e., a physical property or chemical property that does not depend on the amount of the material. These quantitative properties may be used as a metric by which the benefits of one material versus another can be compared, thereby aiding in materials selection.
Gold is a soft metal (MH 2.5–3) [41] that is easily deformed. [42] It has a close-packed face-centred cubic structure (BCN 12). [34] The chemistry of gold is dominated by its +3 valence state; all such compounds of gold feature covalent bonding, [43] as do its stable +1 compounds. [44]
These characteristics contribute to their corrosive nature. [135] All four elements tend to form primarily ionic compounds with metals, [136] in contrast to the remaining nonmetals (except for oxygen) which tend to form primarily covalent compounds with metals.
The alkali metals all have the same crystal structure (body-centred cubic) [10] and thus the only relevant factors are the number of atoms that can fit into a certain volume and the mass of one of the atoms, since density is defined as mass per unit volume. The first factor depends on the volume of the atom and thus the atomic radius, which ...
The "Manual of Metalloids" published in 1864 divided all elements into either metals or metalloids. [235]: 31 Earlier usage in mineralogy, to describe a mineral having a metallic appearance, can be sourced to as early as 1800. [236] Since the mid-20th century it has been used to refer to intermediate or borderline chemical elements. [237]
While all the metals of antiquity but lead occur natively, only gold and silver are commonly found as the native metal. Gold and silver occur frequently in their native form; Mercury compounds are reduced to elemental mercury simply by low-temperature heating (500 °C).