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Nickel ions can act as a cation in salts with many acids, including common oxoacids. Salts of the hexaaqua ion (Ni · 6 H 2 O 2+) are especially well known. Many double salts containing nickel with another cation are known. There are organic acid salts. Nickel can be part of a negatively charged ion (anion) making what is called a nickellate.
Nickel forms a series of mixed oxide compounds which are commonly called nickelates. A nickelate is an anion containing nickel or a salt containing a nickelate anion, or a double compound containing nickel bound to oxygen and other elements. Nickel can be in different or even mixed oxidation states, ranging from +1, +2, +3 to +4.
A wax coating makes this Manila hemp waterproof. A lava lamp is a novelty item that contains wax melted from below by a bulb. The wax rises and falls in decorative, molten blobs. Sealing wax was used to close important documents in the Middle Ages. Wax tablets were used as writing surfaces.
Nickel(II) chloride is made by dissolving nickel or its oxide in hydrochloric acid. It is usually found as the green hexahydrate, whose formula is usually written NiCl 2 ·6H 2 O. When dissolved in water, this salt forms the metal aquo complex [Ni(H 2 O) 6] 2+. Dehydration of NiCl 2 ·6H 2 O gives yellow anhydrous NiCl 2. [48]
Nickel(II) oxide is the chemical compound with the formula NiO. It is the principal oxide of nickel. [4] It is classified as a basic metal oxide. Several million kilograms are produced annually of varying quality, mainly as an intermediate in the production of nickel alloys. [5] The mineralogical form of NiO, bunsenite, is very rare.
In 1803 they obtained a white oxide and called it ceria. Martin Heinrich Klaproth independently discovered the same oxide and called it ochroia. It took another 30 years for researchers to determine that other elements were contained in the two ores ceria and yttria (the similarity of the rare-earth metals' chemical properties made their ...
An oxide (/ ˈ ɒ k s aɪ d /) is a chemical compound containing at least one oxygen atom and one other element [1] in its chemical formula. "Oxide" itself is the dianion (anion bearing a net charge of –2) of oxygen, an O 2– ion with oxygen in the oxidation state of −2. Most of the Earth's crust consists of oxides. Even materials ...
The earliest gold metallurgy is known from the Varna culture in Bulgaria, dating from c. 4600 BC. [6] Silver, copper, tin and meteoric iron can also be found native, allowing a limited amount of metalworking in ancient cultures. [7] Egyptian weapons made from meteoric iron in about 3000 BC were highly prized as "daggers from Heaven". [8]