Emerald nickel

Copper nickel. Emerald nickel Folgorite (See Niocolite) (See Texasite) NiS.EeS 3-5 ... 

Properties. Nickel sulfate hexahydrate [10101 -97-0], NiSo 6H20 is a monoclinic emerald-green crystalline salt that dissolves easily in water and in ethanol. When heated, it loses water and above 800°C decomposes into nickel oxide and SO3. Its density is 2.03 g/cm. ... 

TC-Cyclopentadienyl Nickel Complexes. Nickel bromide dimethoxyethane [29823-39-9] forms bis(cydopentadienyl)nickel [1271 -28-9] upon reaction with sodium cyclopentadienide (63). This complex, known as nickelocene, 7T-(C3H3)2Ni, is an emerald-green crystalline sandwich compound, mp 173°C, density 1.47 g/cm. It is paramagnetic and slowly oxidi2es in air. A number of derivatives of nickelocene are known, eg, methylnickelocene [1292-95-4], which is green and has mp 37°C, and bis( 7t-indenyl)nickel [52409-46-8], which is red, mp 150°C (87,88). 

Dilute mineral acids attack nickel to a varying extent. The metal dissolves readily in dilute nitric acid. Evaporation of the solution forms emerald green crystals of nickel nitrate hexahydrate, Ni(N03)2 61120. 

The hexahydrate forms emerald green monochnic crystals hygroscopic density 2.05 g/cm isomorphous with corresponding cobalt salt melts at 56.7°C loses water on heating, decomposing to nickel oxide very soluble in water aqueous solution acidic soluble in ethanol. 

Beryllium (Be) or Glucinum, at wt 9.02, It grey metal, d 1.842, mp 1284° bp 2767°[Lange( 1956)] mp 1350° bp 1530°(ChemRubHdb) insol in cold w in nitric acid si sol in hot w with decompn sol in HCl, dil sulfuric acid in alks. It does not oxidize at ordinary temp but when heated in the powder form burns brilliantly in air. It does not react with steam even at a red heat. Can be prepd by the electrolysis of a fused mixt of Be chloride with Na or Amm chlorides, or of the fluoride with NaF in a nickel crucible with a carbon anode. Be was discovered ca 1797 in the form of the oxide by Vauquelin as a constituent of the mineral beryl (emerald) (Refs 1-5)... 

Beryllium Beryllium was first detected in 1798 in the gemstones beryl and emerald (BesA SigOis) and was subsequently prepared in pure form in 1828 by the reduction of BeCl2 with potassium. It is obtained today from large commercial deposits of beryl in Brazil and southern Africa. Though beryllium compounds are extremely toxic, particularly when inhaled as dust, the metal is nevertheless useful in forming alloys. Addition of a few percent beryllium to copper or nickel results in hard, corrosion-resistant alloys that are used in airplane engines and precision instruments. 

Ni(C6HsN)4(NCS)2]6,18 81 has been recommended for the ther-mogravimetric determination of nickel or thiocyanate.82-88 The emerald-green chloroform-soluble copper complex [Cu(C5H5N)2-(NCS)2] has been suggested for the detection of copper, pyridine, or thiocyanate.84... 

Nickel is found almost exclusively in the +2 oxidation state in its compounds. Aqueous solutions of nickel(II) salts contain the Ni(H20)62+ ion, which has a characteristic emerald green color. Coordination compounds of nickel(II) will be discussed later in this chapter. Some typical nickel compounds are shown in Table 20.9. 

A nickel-chrome spinel, NiO.CrjOg, has been made artificially in small green crystals. The green colour of emerald, serpentine, possibly sapphire, and other minerals is due to the presence of compounds of chromium, which also occur in rubies, corundums, and spinels. It has been shown that the peculiar spectra of ruby and diamond are due to chromium oxide which has been compelled to vibrate in an abnormal manner, leading to the production of narrow absorption bands. Traces of chromium have been detected in the soot produced by the combustion of coal obtained from deposits at Li ge. Compounds of chromium are not known to play any part in the economy of plants or animals. 

Preparation of Osmium Oxide Pentafluoride.—Osmium oxide pentafluoride was made in several ways, (a) Osmium metal was heated in a stream of oxygen and fluorine (1 2 v/v). The reaction was carried out in a quartz tube with the osmium in a nickel boat, and was initiated by the heat from a small flame. Once started, the reaction sustained itself. The product, which was caught in traps at —183°, was a mixture of an emerald green solid and a pale yellow, more volatile, solid. The difference in volatility of the components of the mixture permitted their separation by trap to trap sublimation under reduced pressure, from a trap held at —16° to receivers cooled with liquid nitrogen. The emerald green solid was retained in the —16° trap. The more volatile, yellow, component proved, from its infrared spectrum, to be osmium hexafluoride. The emerald green solid, m. p. 59-2°, established by infrared spectroscopy, to be free of OsFj, amounted to —50% of the product. 

The nickel complex, Ni ( 5115)2, has been made by the action of the Grignard reagent on nickel (II) acetylacetonate (217) or from potassium cyclopentadienyl and the ammine [Ni(NHs)el (S N)2 in liquid ammonia (58). It forms dark emerald-green crystals which sublime at 80-90° and which, when heated in nitrogen, melt, with decomposition and the formation of a nickel mirror, at 173-174°. It is only slowly oxidized in air, and cold water neither attacks nor dissolves it it is, however, readily soluble in organic liquids. Oxidation of the compound yields an orange-yellow solution containing the ion [Ni( 5H5)2]+, which is stable for a short period in weakly acidic media, and which may be precipitated as the reineckate or tetraphenylborate. 

Emerald-green crystals of the substance NiS04 6H2O are used in nickel plating. What is the chemical name of this compound ... 

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