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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.
Compounds of the metallic elements usually form simple aqua ions with the formula [M(H 2 O) n] z+ in low oxidation states. With the higher oxidation states the simple aqua ions dissociate losing hydrogen ions to yield complexes that contain both water molecules and hydroxide or oxide ions, such as the vanadium (IV) species [VO(H 2 O) 5 ] 2+ .
The chemistry of astatine in aqueous solution is mainly characterised by the formation of various anionic species. [484] Most of its known compounds resemble those of iodine, [485] which is a halogen and a nonmetal. [486] Such compounds include astatides (XAt), astatates (XAtO 3), and monovalent interhalogen compounds. [487]
The chemistry of silver is dominated by its +1 valence state in which it shows generally similar physical and chemical properties to compounds of thallium, a main group metal, in the same oxidation state. [35] It tends to bond covalently in most of its compounds. [36] The oxide (Ag 2 O) is amphoteric, with basic properties predominating. [37]
An intermetallic compound is a type of metallic alloy that forms an ordered solid-state compound between two or more metallic elements. Intermetallics are generally hard and brittle, with good high-temperature mechanical properties.
'Nonmolecular' would perhaps be a better term. Metallic bonding is mostly non-polar, because even in alloys there is little difference among the electronegativities of the atoms participating in the bonding interaction (and, in pure elemental metals, none at all). Thus, metallic bonding is an extremely delocalized communal form of covalent bonding.
Metallic solids have, by definition, no band gap at the Fermi level and hence are conducting. Solids with purely metallic bonding are characteristically ductile and, in their pure forms, have low strength; melting points can [inconsistent] be very low (e.g., Mercury melts at 234 K (−39 °C). These properties are consequences of the non ...
Metallic hydrogen is a phase of hydrogen in which it behaves like an electrical conductor. This phase was predicted in 1935 on theoretical grounds by Eugene Wigner and Hillard Bell Huntington . [ 1 ]