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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.
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 ...
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.
'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.
Metallurgy derives from the Ancient Greek μεταλλουργός, metallourgós, "worker in metal", from μέταλλον, métallon, "mine, metal" + ἔργον, érgon, "work" The word was originally an alchemist's term for the extraction of metals from minerals, the ending -urgy signifying a process, especially manufacturing: it was discussed in this sense in the 1797 Encyclopædia ...
Their respective densities of 1.7, 2.7, and 4.5 g/cm 3 can be compared to those of the older structural metals, like iron at 7.9 and copper at 8.9 g/cm 3. The most common lightweight metals are aluminium [12] [13] and magnesium [14] [15] alloys. Schematic appearance of round metal bars after tensile testing. (a) Brittle fracture (b) Ductile ...
It has the weakest metallic bonding of all, as indicated by its bonding energy (61 kJ/mol) and melting point (−39 °C) which, together, are the lowest of all the metallic elements. [66] [n 7] Solid mercury (MH 1.5) [67] has a distorted crystalline structure, [68] with mixed metallic-covalent bonding, [69] and a BCN of 6. "All of the [Group 12 ...
Structure of [Cp*Al] 4, a main group organometallic compound. Main group organometallic chemistry concerns the preparation and properties of main-group elements directly bonded to carbon. The inventory is large. The compounds exhibit a wide range of properties, including ones that are water-stable and others that are pyrophoric. [1]