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Stock nomenclature. Stock nomenclature for inorganic compounds is a widely used system of chemical nomenclature developed by the German chemist Alfred Stock and first published in 1919. In the "Stock system", the oxidation states of some or all of the elements in a compound are indicated in parentheses by Roman numerals. [1][2]
A clock face with the Roman numerals typical for clocks, in Bad Salzdetfurth, Germany. While subtractive notation for 4, 40 and 400 (IV, XL and CD) has been the usual form since Roman times, additive notation to represent these numbers (IIII, XXXX and CCCC) [9] continued to be used, including in compound numbers like 24 (XXIIII), [10] 74 (LXXIIII), [11] and 490 (CCCCLXXXX). [12]
The numbers 200-900 would be confused easily with 22 to 29 if they were used in chemistry. khīlioi = 1000, diskhīlioi = 2000, triskhīlioi = 3000, etc. 13 to 19 are formed by starting with the Greek word for the number of ones, followed by και (the Greek word for 'and'), followed by δέκα (the Greek word for 'ten').
v. t. e. The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows ("periods") and columns ("groups"). It is an icon of chemistry and is widely used in physics and other sciences. It is a depiction of the periodic law, which states that when the elements are arranged in ...
The group numberings with Roman numbers and "A" and "B" suffixes (like VIIA, VIII) should not be used, as they are outdated and ambiguous. For example, in the CAS scheme "group VIIB" denotes manganese group (group 7), while in the old IUPAC scheme it denotes halogen group (group 17). If they are used at all, context should clarify (disambiguate ...
Chemical nomenclature. Chemical nomenclature is a set of rules to generate systematic names for chemical compounds. The nomenclature used most frequently worldwide is the one created and developed by the International Union of Pure and Applied Chemistry (IUPAC). IUPAC Nomenclature ensures that each compound (and its various isomers) have only ...
The Roman numerals in fact show the oxidation number, but in simple ionic compounds (i.e., not metal complexes) this will always equal the ionic charge on the metal. For a simple overview see [1] Archived 2008-10-16 at the Wayback Machine , for more details see selected pages from IUPAC rules for naming inorganic compounds Archived 2016-03-03 ...
In the periodic table of the elements, each column is a group. In chemistry, a group (also known as a family) [1] is a column of elements in the periodic table of the chemical elements. There are 18 numbered groups in the periodic table; the 14 f-block columns, between groups 2 and 3, are not numbered. The elements in a group have similar ...