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Coinage metals – Various metals used to mint coins, primarily the group 11 elements Cu, Ag, and Au. Earth metal – Old historic term, usually referred to the metals of groups 3 and 13, although sometimes others such as beryllium and chromium are included as well. Heavy metals – Variously-defined group of metals, on the base of their ...
118 chemical elements have been identified and named officially by IUPAC.A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z).
a Group 1 is composed of hydrogen (H) and the alkali metals. Elements of the group have one s-electron in the outer electron shell. Hydrogen is not considered to be an alkali metal as it is not a metal, though it is more analogous to them than any other group. This makes the group somewhat exceptional.
The old IUPAC system was frequently used in Europe, while the CAS is most common in America. The new IUPAC scheme was developed to replace both systems as they confusingly used the same names to mean different things. The new system simply numbers the groups increasingly from left to right on the standard periodic table.
The naming rules promulgated by IUPAC in 2002 declared that all newly discovered elements should have names ending in -ium, for linguistic consistency. [40] In 2016, this was amended so that elements in the halogen and noble gas groups would receive the traditional -ine and -on suffixes.
A few groups have IUPAC-approved names, called trivial name, that may also be used: alkali metal = group 1 except hydrogen alkaline earth metal = group 2 triels = group 13 tetrels = group 14 pnictogen = group 15 (earlier pentels) chalcogen = group 16 halogen = group 17 noble gas = group 18
In addition, groups 8, 9 and 10 used to be treated as one triple-sized group, known collectively in both notations as group VIII. In 1988, the new IUPAC (International Union of Pure and Applied Chemistry) naming system (1–18) was put into use, and the old group names (I–VIII) were deprecated. [23
The positive ion retains its element name whereas for a single non-metal anion the ending is changed to -ide. Example: sodium chloride, potassium oxide, or calcium carbonate. When the metal has more than one possible ionic charge or oxidation number the name becomes ambiguous. In these cases the oxidation number (the same as the charge) of the ...