Nickel IV oxide

Oxides of the alkali and alkaline earth metals and nickel(II) oxide incandesce in cold fluorine, and iron(II) oxide when warmed. Nickel(IV) oxide also bums in fluorine. 

Manganese trichloride oxide, 4141 Mercury(I) oxide , 4613 Mercury(II) oxide, 4605 Molybdenum(IV) oxide, 4716 Molybdenum(VI) oxide, 4717 Nickel(II) oxide, 4821 Nickel(III) oxide, 4823 Nickel(IV) oxide, 4822 Niobium(V) oxide, 4818 Osmium(IV) oxide, 4833 Osmium(VIII) oxide, 4858 Palladium(II) oxide, 4825 Palladium(III) oxide, 4848 Palladium(IV) oxide, 4835... 

Another type of rechargeable battery is the nickel-cadmium, Ni-Cd, battery, cadmium acts as an anode, and nickel (IV) oxide is reduced to nickel (II) hydroxide, Ni(0H)2, at the cathode. As in the lead storage battery, the nickel-cadmium type can be recharged indefinitely. 

The oxidative fluorination of C-H bonds of the side chain in toluene l43 and ethylbenzene derivatives 4 has been reported.45 4fi These alkyl aromatics bearing electronegative substituents are cleanly fluorinated on the alkyl group in liquid hydrogen fluoride in the presence of lead(IV) oxide,45 nickel(IV) oxide,45 silver(II) fluoride,46 cobalt(III) fluoride,46 or cobalt(III) acetate.46... 

The anode is cadmium, and the cathode is nickel(IV) oxide. The electrolytic solution is basic. The discharge reactions that occur in a nicad battery are... 

Toluene derivatives bearing electronegative substituents are fluorinated on the methyl group when reacted with lead(IV) oxide, nickel(IV) oxide, eobalt(III) fluoride, cobalt(III) acetate, silver(II) fluoride, or silver(Il) oxide in liquid hydrogen fluoride.02 64 The product obtained is dependent on the substrate and the metal oxidant employed, with benzyl fluorides 1 or (difluoromethyl)benzenes 2 as the major products. 

Nickel forms only one series of salts, containing the nickel ion, Ni ". A few compounds of nickel with higher oxidation number are known of these the nickel(IV) oxide, NiOa, is important. 

In alkaline solution nickel(ll) hydroxide can be oxidized to a hydrated nickel(IV) oxide, Ni02vvH20. This reaction is used in the Edison storage cell. The electrodes of this cell are plates coated with Ni02-A H20 and metallic iron, which are converted on discharge of the cell into nickel(Il) hydroxide and ferrous hydroxide, respectively. The electrolyte in this cell is a solution of sodium hydroxide. 

Complete reduction of the azepine ring to hexahydroazepine has been effected with hydrogen and palladium,40 or platinum,135 239 catalysts. For example, ethyl 1 f/-azepine-l-carboxylate is reduced quantitatively at room temperature to ethyl hexahydroazepine-l-carboxylate (92% bp 118 —120 3C).134 136 TV-Phenyl-S/Z-azepin -amine (1), however, with platinum(IV) oxide and hydrogen in methanol yields the hexahydroazepine 2 in which the amidine unit is preserved in the final product.34 The same result is obtained using 5% palladium/barium carbonate, or 2 % palladium/Raney nickel, as catalyst. 

Kolbel et al. (K16) examined the conversion of carbon monoxide and hydrogen to methane catalyzed by a nickel-magnesium oxide catalyst suspended in a paraffinic hydrocarbon, as well as the oxidation of carbon monoxide catalyzed by a manganese-cupric oxide catalyst suspended in a silicone oil. The results are interpreted in terms of the theoretical model referred to in Section IV,B, in which gas-liquid mass transfer and chemical reaction are assumed to be rate-determining process steps. Conversion data for technical and pilot-scale reactors are also presented. 

Violence of reaction depends on concentration of acid and scale and proportion of reactants. The following observations were made with additions to 2-3 drops of ca. 90% acid. Nickel powder, becomes violent mercury, colloidal silver and thallium powder readily cause explosions zinc powder causes a violent explosion immediately. Iron powder is ineffective alone, but a trace of manganese dioxide promotes deflagration. Barium peroxide, copper(I) oxide, impure chromium trioxide, iridium dioxide, lead dioxide, manganese dioxide and vanadium pentoxide all cause violent decomposition, sometimes accelerating to explosion. Lead(II) oxide, lead(II),(IV) oxide and sodium peroxide all cause an immediate violent explosion. 

Recently, the crystal structure of a nickel(II) complex with a tridentate silyl ligand has been reported [20]. The structure in the solid state shows an //2-(Si-H) binding to nickel, with a Ni-H distance of 1.47 A NMR spectra of the complex in solution at -80 °C suggest the formation of a nickel(IV) hydride species through oxidative addition of the silyl-hydrogen to nickel [20]. 

Nickel(II) complexes of a variety of bidentate sulfoxide ligands have been reported (326,378,413) and [NiL3][C104]2 species reported where L is the unusual bidentate ligand 2-(ethysulfinyl)pyridine-iV-oxide. Bidentate 0,0-coordination via sulfoxide and pyridine-N-oxide donors is assigned from infrared data (63). 

NiCb + 2C6H5CSSH- Ni (C6H5CSS)2 + 2HC1 The product oxidizes readily to a violet dimeric nickel(IV) complex. 

Secondary cells are voltaic cells that can be recharged repeatedly. The lead storage battery and nickel-cadmium cell are examples of secondary cells. The lead storage battery consists of six voltaic cells. Its electrodes are lead alloy plates, which take the form of a grill, filled with spongy lead metal. The cathode consists of another group of plates filled with lead (IV) oxide, P6O2. Dilute sulfuric acid is the electrolyte of the cell. When the battery delivers a current, the lead is oxidized to lead ions, which combine with sulfate fS0 7 ions of the electrolyte to cover the lead electrode. 

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