Search results
Results From The WOW.Com Content Network
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 society ...
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 refining. Its chief use is as feedstock for ethylene production.
History. Throughout the history of chemistry, many chemical elements have been discovered. In the 19th century, Dmitri Mendeleev formulated the periodic table, a table of elements which describes their structure. Because elements have been discovered at various times and places, from antiquity through the present day, their names have derived ...
Chemistry, from the ancient Egyptian word "khēmia" meaning transmutation of earth, is the science of matter at the atomic to molecular scale, dealing primarily with collections of atoms, such as molecules, crystals, and metals. Thus, according to Budge and others, chemistry derives from an Egyptian word khemein or khēmia, "preparation of ...
The protoscience of chemistry, alchemy, was unsuccessful in explaining the nature of matter and its transformations. However, by performing experiments and recording the results, alchemists set the stage for modern chemistry. The history of chemistry is intertwined with the history of thermodynamics, especially through the work of Willard Gibbs.
For example, one can deduce that 1-chloropropane has a Chlorine atom on the first carbon in the 3-carbon propane chain. History "Well being" of standardizing science by the nomenclature of scientific terms, measurements, and symbols was one of the primary reasons as to the founding of the organization.
In the history of chemistry, the chemical revolution, also called the first chemical revolution, was the reformulation of chemistry during the seventeenth and eighteenth centuries, which culminated in the law of conservation of mass and the oxygen theory of combustion. During the 19th and 20th century, this transformation was credited to the ...
Polyurethane synthesis, wherein the urethane groups −NH−(C=O)−O− link the molecular units A kitchen sponge made of polyurethane foam. Polyurethane (/ ˌ p ɒ l i ˈ jʊər ə ˌ θ eɪ n,-j ʊəˈr ɛ θ eɪ n /; often abbreviated PUR and PU) refers to a class of polymers composed of organic units joined by carbamate (urethane) links.