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Zinc oxide is an inorganic compound with the formula Zn O.It is a white powder which is insoluble in water. ZnO is used as an additive in numerous materials and products including cosmetics, food supplements, rubbers, plastics, ceramics, glass, cement, lubricants, [12] paints, sunscreens, ointments, adhesives, sealants, pigments, foods, batteries, ferrites, fire retardants, semi conductors ...
An early example of zinc white's use in painting [1]: 183 Zinc white is an inorganic pigment composed of zinc oxide that has been used by painters since the late eighteenth century. [1] Alongside lead and titanium white, it is among the three most prominent white pigments that are commercially available today. [1]
All three found an unknown metal in a sample of zinc oxide from Silesia, but the name that Stromeyer gave became the accepted one. [119] 34 Selenium: 1817 J. Berzelius and G. Gahn: 1817 J. Berzelius and G. Gahn While working with lead they discovered a substance that they thought was tellurium, but realized after more investigation that it was ...
Zinc oxide is used to protect rubber polymers and plastics from ultraviolet radiation (UV). [126] The semiconductor properties of zinc oxide make it useful in varistors and photocopying products. [145] The zinc zinc-oxide cycle is a two step thermochemical process based on zinc and zinc oxide for hydrogen production. [146]
Roasting converts the zinc sulfide concentrate produced during processing to zinc oxide. [80] For further processing two basic methods are used: pyrometallurgy or electrowinning . Pyrometallurgy processing reduces zinc oxide with carbon or carbon monoxide at 950 °C (1,740 °F) into the metal, which is distilled as zinc vapor. [ 81 ]
In the 18th and 19th centuries large ore mines could be found near the German village of Breinigerberg. During the early 19th century it was discovered that what had been thought to be one ore was actually two distinct minerals: Zinc carbonate ZnC O 3 or smithsonite and; Zinc silicate Zn 4 Si 2 O 7 (OH) 2 ·H 2 O or hemimorphite.
The ancient burial site was found near Magdeburg, a city about 100 miles west of Berlin. Excavations at the site are ongoing and scheduled to end in April, officials said.
Zinc melts at 420 °C (787 °F), [21] but importantly boils at 907 °C (1665 °F), a temperature below the melting point of silver. Consequently, at the temperatures needed to reduce zinc oxide to the metal, the metal is already gaseous. [23] [24] Arsenic sublimes at 615 °C (1137 °F), passing directly from the solid state to the gaseous state ...