Chemical element
A chemical element, often called simply element, is the class of atoms which contain the same number of protons.
Chemical symbols
Specific chemical elements
Before chemistry became a science, alchemists had designed arcane symbols for both metals and common compounds. These were however used as abbreviations in diagrams or procedures; there was no concept of one atoms combining to form molecules. With his advances in the atomic theory of matter, John Dalton devised his own simpler symbols, based on circles, which were to be used to depict molecules. These were superseded by the current typographical system in which chemical symbols are not used as mere abbreviations though each consists letters of the Latin alphabet - they are symbols intended to be used by peoples of all languages and alphabets.
Related Topics:
Alchemists - John Dalton - Latin alphabet
~ ~ ~ ~ ~ ~ ~ ~ ~ ~
The first of these symbols were intended to be fully international, for they were based on the Latin abbreviations of the names of metals: Fe comes from Ferrum; Ag from Argentum. The symbols were not followed by a period (full stop) as abbreviations were. Besides a name, later chemical elements are also given a unique chemical symbol, based on the name of the element, not necessarily derived from the colloquial English name. (e.g., sodium has chemical symbol 'Na' after the Latin natrium). The same applies to "W" (wolfram) for Tungsten , "Hg" (Hydrargyrum) for mercury and "K" for potassium. Stricly taken, a symbol like Tu for tungsten or M or Me for mercury seems to be more logical.
Related Topics:
Latin - Sodium - Tungsten - Hydrargyrum - Potassium
~ ~ ~ ~ ~ ~ ~ ~ ~ ~
Chemical symbols are understood internationally when element names might need to be translated. There are sometimes differences; for example, the Germans have used "J" instead of "I" for iodine, so the character would not be confused with a roman numeral.
~ ~ ~ ~ ~ ~ ~ ~ ~ ~
The first letter of a chemical symbol is always capitalized, as in the preceding examples, and the subsequent letters, if any, are always minuscule (small letters).
~ ~ ~ ~ ~ ~ ~ ~ ~ ~
General chemical symbols
There are also symbols for series of chemical elements, for comparative formulas. These are one capital letter in length, and the letters are reserved so they are not permitted to be given for the names of specific elements. For example, an "X" is used to indicate a variable group amongst a class of compounds (though usually a halogen), while "R" is used for a radical (not to be confused with radical_(chemistry), meaning a compound structure such as a hydrocarbon chain. The letter "Q" is reserved for "heat" in a chemical reaction. "Y" is also often used as a general chemical symbol, although it is also the symbol of yttrium. "Z" is also frequently used as a general variable group. "L" is used to represent a general ligand in inorganic and organometallic chemistry. "M" is also often used in place of a general metal.
Related Topics:
Halogen - Radical_(chemistry) - Yttrium - Ligand
~ ~ ~ ~ ~ ~ ~ ~ ~ ~
Nonelement symbols
Nonelements, especially in organic and organometallic chemistry, often acquire symbols which are inspired by the elemental symbols. A few examples:
~ ~ ~ ~ ~ ~ ~ ~ ~ ~
Cy - cyclohexyl; Ph - phenyl; Bz - benzoyl; Bn - benzyl; Cp - Cyclopentadiene; Pr - propyl; Me - methyl; Et - ethyl; Tf - triflate; Ts - tosyl.
Related Topics:
Cyclohexyl - Phenyl - Benzoyl - Benzyl - Cyclopentadiene - Propyl - Methyl - Ethyl - Triflate - Tosyl
~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~ Table of Content ~
| ► | Introduction |
| ► | Nomenclature |
| ► | Chemical symbols |
| ► | See also |
| ► | External links |
~ What's Hot ~
~ Community ~
| ► | History Forum Come and discuss about History, Civilizations, Historical Events and Figures |
| ► | History Web-Ring A community of sites, blogs and forums dedicated to History. Do not hesitate to submit your site. |
and are licensed under the GNU Free Documentation License.
Lexicon - Privacy Policy - Spiritus-Temporis.com ©2005.