jedzenie: Aluminium

Evidence: 100 • authority: 72

Aluminium (the Commonwealth and preferred IUPAC name) or aluminum (North American English) is a chemical element; it has symbol Al and atomic number 13. It has a density lower than other common metals, about one-third that of steel. Aluminium has a great affinity toward oxygen, forming a protective layer of oxide on the surface when exposed to air. It visually resembles silver, both in its color and in its great ability to reflect light. It is soft, nonmagnetic, and ductile. It has one stable isotope, 27Al, which is highly abundant, making aluminium the 12th-most abundant element in the universe. The radioactivity of 26Al leads to it being used in radiometric dating. Chemically, aluminium i…

Evidence: 95 • authority: 72

Aluminium (or aluminum) metal is very rare in native form, and the process to refine it from ores is complex, so for most of human history it was unknown. However, the compound alum has been known since the 5th century BCE and was used extensively by the ancients for dyeing. During the Middle Ages, its use for dyeing made it a commodity of international commerce. Renaissance scientists believed that alum was a salt of a new earth; during the Age of Enlightenment, it was established that this earth, alumina, was an oxide of a new metal. Discovery of this metal was announced in 1825 by Danish physicist Hans Christian Ørsted, whose work was extended by German chemist Friedrich Wöhler. Aluminiu…

Evidence: 45 • authority: 72

The Deville–Pechiney process, also known as the Le Châtelier process, was the first industrial process used to produce alumina from bauxite. The Frenchman Henri Sainte-Claire Deville invented the process in 1859, in collaboration with Louis Le Châtelier. In 1860, Deville sold his aluminium interests to Henri Merle, a founder of Compagnie d'Alais et de la Camargue, later known as Pechiney. It is based on the extraction of alumina with sodium carbonate. The first stage is the calcination of the bauxite at 1200 °C with sodium carbonate and coke. The alumina is converted in sodium aluminate. Iron oxide remains unchanged and silica forms a polysilicate. In the second stage sodium hydroxide solut…

Evidence: 45 • authority: 72

Henri Étienne Sainte-Claire Deville (11 March 1818 – 1 July 1881) was a French chemist. He was born in the island of St Thomas in the Danish West Indies, where his father was French consul. Together with his elder brother Charles, he was educated in Paris at the collège Rollin. In 1844, having graduated as a doctor of medicine and doctor of science, he was appointed to organize the new faculty of science at Besançon, where he acted as dean and professor of chemistry from 1845 to 1851. Returning to Paris in the latter year he succeeded Antoine Jérôme Balard at the École Normale, and in 1859 became professor at the Sorbonne in place of J. B. A. Dumas, for whom he had begun to lecture in 1853.…