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The history of aluminium was shaped by the usage of its compound alum. The first written record of alum was in the 5th century BCE by Greek historian Herodotus. [2] The ancients used it as a dyeing mordant, in medicine, in chemical milling, and as a fire-resistant coating for wood to protect fortresses from enemy arson. [3] Aluminium metal was ...
Aluminium (or aluminum in North American English) is a chemical element; it has symbol Al and atomic number 13. Aluminium has a density lower than that of other common metals, about one-third that of steel. It has a great affinity towards oxygen, forming a protective layer of oxide on the surface when exposed to air.
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
In 1802 the term "metalloids" was introduced for elements with the physical properties of metals but the chemical properties of non-metals. [194] However, in 1811, the Swedish chemist Berzelius used the term "metalloids" [ 195 ] to describe all nonmetallic elements, noting their ability to form negatively charged ions with oxygen in aqueous ...
The metals of antiquity are the seven metals which humans had identified and found use for in prehistoric times in Africa, Europe and throughout Asia: [1] gold, silver, copper, tin, lead, iron, and mercury. Zinc, arsenic, and antimony were also known during antiquity, but they were not recognised as distinct metals until later.
This is an accepted version of this page This is the latest accepted revision, reviewed on 28 January 2025. Development of the table of chemical elements The American chemist Glenn T. Seaborg —after whom the element seaborgium is named—standing in front of a periodic table, May 19, 1950 Part of a series on the Periodic table Periodic table forms 18-column 32-column Alternative and extended ...
(The Ebers papyrus was written c. 1550 BC, but is believed to have been copied from earlier texts.) [25] [26] Designated as one of the two elements of which all metals are composed in the sulfur-mercury theory of metals, first described in pseudo-Apollonius of Tyana's Sirr al-khaliqa ('Secret of Creation') and in the works attributed to Jabir ...
It is therefore, arguably, an exception to the mnemonic that elements adjacent to the metal–nonmetal dividing line are metalloids. [430] [n 45] Stott [432] labels aluminium as a weak metal. It has the physical properties of a metal but some of the chemical properties of a nonmetal.