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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.
Metal ions and metallic compounds are often used in medical treatments and diagnoses. [18] Compounds containing metal ions can be used as medicine, such as lithium compounds and auranofin . [ 19 ] [ 20 ] Metal compounds and ions can also produce harmful effects on the body due to the toxicity of several types of metals. [ 18 ]
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 most commonly known and studied bioinorganic iron compounds (biological iron molecules) are the heme proteins: examples are hemoglobin, myoglobin, and cytochrome P450. [1] These compounds participate in transporting gases, building enzymes, and transferring electrons. [5] Metalloproteins are a group of proteins with metal ion cofactors.
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.
When several metals are linked by metal-metal bonds, the compound or ion is called a metal cluster. Many metal clusters contain several unsupported M–M bonds. Some examples are M 3 (CO) 12 (M = Ru, Os) and Ir 4 (CO) 12. A subclass of unsupported metal–metal bonded arrays are linear chain compounds. In such cases the M–M bonding is weak as ...
Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and sometimes broadened to include metalloids like boron, silicon, and selenium, as well.