Nickel hydrate

Nickel hydrate, usually 5-10% cobalt added, serves as the active material and is mixed with a conductive carbon, e g., graphite. The active mass is mixed with an inert organic binder such as polyethylene or poly(tetrafluoroethyleiie) (TFE). The resultant mass is rolled into sheets on a compounding mill or pressed into electrodes as a dry powder on a nickel grid. 

Nickel hydrate Nickel (II) hydroxide. See Nickel hydroxide (ous)... 

CAS 12054-48-7 EINECS/ELINCS 235-008-5 Synonyms Green nickel oxide Nickel dihydroxide Nickel hydrate Nickel (II) hydroxide Nickelous hydroxide Empincal H2NI02 Formula Ni(OH)2... 

The higher iodides, however, tend to be unstable and decomposition occurs to the lower iodide (PI5 -> PI3). Anhydrous chlorides and bromides of some metals may also be prepared by the action of acetyl (ethanoyl) halide on the hydrated ethanoate (acetate) in benzene, for example cobalt(II) and nickel(II) chlorides ... 

Nickel forms yellow anhydrous halides NiXjlX = F. Cl. Br) and a black iodide Nil2 all these halides are made by direct combination of the elements, and the chloride by reaction of sulphur dichloride oxide with the hydrated salt. All dissolve in water to give green solutions from which the hydrates can be crystallised the solutions contain the ion [NifHjOls], and the chloride crystallises as NiCl2.6H2O, nickel(II) chloride hexahydrate. 

Addition of an alkali metal hydroxide solution to an aqueous solution of a nickel(II) salt precipitates a finely-divided green powder. nickel(II) hydroxide NilOHfj on heating this gives the black oxide. NiO. which is also obtained by heating nickel(II) carbonate or the hydrated nitrate. Black nickel(II) sulphide, NiS, is obtained by passing hydrogen sulphide into a solution of a nickel(II) salt. 

Nickel forms a green hydrated sulphate NiS04. TH O and the double sulphate (NH4),S04. NiS04.6HtO (cf. iron, p. 396). 

In contrast to the sulfide ores, the lateritic ores were formed over long periods of time as a result of weathering of exposed nickel-containing rocks. The lateritic weathering process resulted in nickel solutions that were redeposited elsewhere in the form of oxides or siUcates. One type of laterite is nickeliferous limonitic iron laterite (Ee, Ni)O(OH) which consists primarily of hydrated iron oxide in which the nickel is dispersed in soHd solution. 

Properties. Nickel forms anhydrous as well as hydrated haHdes. The properties of the anhydrous salts are given in Table 1. 

Electrodes. A number of different types of nickel oxide electrodes have been used. The term nickel oxide is common usage for the active materials that are actually hydrated hydroxides at nickel oxidation state 2+, in the discharged condition, and nickel oxide hydroxide [12026-04-9] NiO OH, nickel oxidation state 3+, in the charged condition. Nickelous hydroxide [12034-48-7J, Ni(OH)2, can be precipitated from acidic solutions of bivalent nickel... 

The process by which porous sintered plaques are filled with active material is called impregnation. The plaques are submerged in an aqueous solution, which is sometimes a hot melt in a compound s own water of hydration, consisting of a suitable nickel or cadmium salt and subjected to a chemical, electrochemical, or thermal process to precipitate nickel hydroxide or cadmium hydroxide. The electrochemical (46) and general (47) methods of impregnating nickel plaques have been reviewed. 

Hypobromites, the salts of hypobromous acid, do not keep well because they gradually disproportionate to bromide and bromate. Solutions are best prepared as needed from bromine and alkafl with cooling. Because disproportionation is catalyzed by cobalt, nickel, and copper (70), these impurities should be avoided. SoHd alkaline earth hypobromites, or more properly, bromide hypobromites such as calcium bromide hypobromite [67530-61 CaBr(OBr), have been known for many years, but the pure crystalline hydrates sodium hypobromite pentahydrate [13824-96-9] NaOBr 5H20, and potassium hypobromite tribydrate [13824-97-0], KOBr 3H20, were not described until 1952 (71). Hypobromites are strong bleaching agents, similar to hypochlorites. 

Nickel (II) acetate (4H2O) [6018-89-9] M 248.9, d 1.744, pK / 8.94 (from Ni + hydrolysis). Recryst from aqueous AcOH as the green tetrahydrate. Soluble in 6 parts of H2O. It forms lower hydrates and should be kept in a well closed container. [ZAnorg Allg Chem 343 92 1966.]... 

The azido mesylate is suspended in absolute ethanol and 80% hydrazine hydrate (3 ml/g of azido mesylate). A small amount (tip of spatula) of Raney nickel (W-2 grade or commercial 50% sponge nickel catalyst from W. R. 

A reagent of nickel boridei/hydiazine hydrate reduces both aromadc and aliphatic nitro compotmds. For example, it has been used for synthesis ofd-fbenzyloxyiindole and -alkyltryp-... 

Jfickeloxydul, n. nickelous oxide, nickel(II) oxide, NiO. -hydrat, n, nickelous hydroxide, nickel (II) hydroxide, -salz, n. nickelous salt, nickel(II) salt, -verbindung,/. nickelous compound, nickel(II) compound. Nickelpapier, n. nickel foil, nickelplattiert, a. nickel-plated. 

Dinitroarenes containing substituents such as hydroxyl or amino groups are reduced with 3 mol equiv of hydrazine hydrate in the presence of Raney nickel to afford selectively a compound in which only one nitro group is reduced. In general, the main product is derived by reduction of the more hindered nitro function. For example,... 

Most authorities nowadays accept the view that passivity of nickel, as of most other metals, is due to the formation of a film of oxide or hydrated... 

In acidic solutions the film has been reported to be hydrated nickel oxyhydroxide, NiOy(OH)2 2y. MH2O in which y is greater in the passive film than in the pre-passive film formed in the active region . In neutral solutions films consisting of NiO and Ni(OH)2 possibly with some NiO have been described. In alkaline solutions NifOHlj has been reported . 

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