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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 ...
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
Zinc oxide is used to protect rubber polymers and plastics from ultraviolet radiation (UV). [125] The semiconductor properties of zinc oxide make it useful in varistors and photocopying products. [144] The zinc zinc-oxide cycle is a two step thermochemical process based on zinc and zinc oxide for hydrogen production. [145]
Zinc compounds, like those of main group elements, are mostly colourless. Exceptions occur when the compound contains a coloured anion or ligand. However, zinc selenide and zinc telluride are both coloured due to charge-transfer processes. Zinc oxide turns yellow when heated due to the loss of some oxygen atoms and formation of a defect structure
Zinc oxide (ZnO) nanostructures are structures with at least one dimension on the nanometre scale, composed predominantly of zinc oxide. They may be combined with other composite substances to change the chemistry, structure or function of the nanostructures in order to be used in various technologies.
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]
Zinc hydroxide Zn 2 is an inorganic chemical compound. It also occurs naturally as 3 rare minerals: wülfingite (orthorhombic), ashoverite and sweetite (both tetragonal). Like the hydroxides of other metals, such as lead , aluminium , beryllium , tin and chromium , Zinc hydroxide (and Zinc oxide ), is amphoteric .
Zinc nitrate is usually prepared by dissolving zinc metal, zinc oxide, or related materials in nitric acid: Zn + 2 HNO 3 → Zn(NO 3) 2 + H 2 ZnO + 2 HNO 3 → Zn(NO 3) 2 + H 2 O. These reactions are accompanied by the hydration of the zinc nitrate. The anhydrous salt arises by the reaction of anhydrous zinc chloride with nitrogen dioxide: [1]