Search results
Results From The WOW.Com Content Network
Thegn. Ivory seal of Godwin, an unknown thegn – first half of eleventh century, British Museum. In later Anglo-Saxon England, a thegn ( pronounced / θeɪn /; Old English: þeġn) or thane [1] (or thayn in Shakespearean English) was an aristocrat who owned substantial land in one or more counties. Thanes ranked at the third level in lay ...
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 ...
Ethane ( US: / ˈɛθeɪn / ETH-ayn, UK: / ˈiː -/ EE-) is a naturally occurring organic chemical compound with chemical formula C. 2H. 6. At standard temperature and pressure, ethane is a colorless, odorless gas. Like many hydrocarbons, ethane is isolated on an industrial scale from natural gas and as a petrochemical by-product of petroleum ...
The Geneva Nomenclature of 1892 was created as a result of many other meetings in the past, the first of which was established in 1860 by August Kekulé. Another entity called the International Association of Chemical Societies (IACS) existed, and on 1911, gave vital propositions the new one should address: [ 2] Measures required to prevent ...
Nomenclature. Nomenclature ( UK: / noʊˈmɛŋklətʃər, nə -/, US: / ˈnoʊmənkleɪtʃər /) [ 1][ 2] is a system of names or terms, or the rules for forming these terms in a particular field of arts or sciences. [ 3] The principles of naming vary from the relatively informal conventions of everyday speech to the internationally agreed ...
The history of the periodic table is also a history of the discovery of the chemical elements. The first person in recorded history to discover a new element was Hennig Brand, a bankrupt German merchant. Brand tried to discover the philosopher's stone —a mythical object that was supposed to turn inexpensive base metals into gold.
Chemistry. The 1871 periodic table constructed by Dmitri Mendeleev. The periodic table is one of the most potent icons in science, lying at the core of chemistry and embodying the most fundamental principles of the field. The history of chemistry represents a time span from ancient history to the present.
Heterocyclic organic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of organic heterocycles. [2] Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. More than half of ...