Cobaltate -, silver potassium

Cobalt compounds have been in use for centuries, notably as pigments ( cobalt blue ) in glass and porcelain (a double silicate of cobalt and potassium) the metal itself has been produced on an industrial scale only during the twentieth century. Cobalt is relatively uncommon but widely distributed it occurs biologically in vitamin B12 (a complex of cobalt(III) in which the cobalt is bonded octahedrally to nitrogen atoms and the carbon atom of a CN group). In its ores, it is usually in combination with sulphur or arsenic, and other metals, notably copper and silver, are often present. Extraction is carried out by a process essentially similar to that used for iron, but is complicate because of the need to remove arsenic and other metals. 

In a second series of six experiments the chlorine in the neutral chloride was determined volumetrically by Volhard s method after removing the cobalt, with potassium carbonate. The ratio of cobalt to silver was thus established and checked by two experiments in which cobalt was allowed to displace silver from silver sulphate solution ... 

Silicon Alkali carbonates, calcium, chlorine, cobalt(II) fluoride, manganese trifluoride, oxidants, silver fluoride, sodium-potassium alloy... 

Monofluorophosphates of ammonium, lithium, sodium, potassium, silver, calcium, strontium, barium, mercury, lead, and benzidine have been described (70) as have the nickel, cobalt, and ziac salts (71), and the cadmium, manganese, chromium, and iron monofluorophosphates (72). Many of the monofluorophosphates are similar to the corresponding sulfates (73). 

At room temperature, sulfur unites readily with copper, silver, and mercury and vigorously with sodium, potassium, calcium, strontium, and barium to form sulfides. Iron, chromium, tungsten, nickel, and cobalt react much less readily. In a finely divided state, zinc, tin, iron, and aluminum react with sulfur on heating (19). 

The reaction is a sensitive one, but is subject to a number of interferences. The solution must be free from large amounts of lead, thallium (I), copper, tin, arsenic, antimony, gold, silver, platinum, and palladium, and from elements in sufficient quantity to colour the solution, e.g. nickel. Metals giving insoluble iodides must be absent, or present in amounts not yielding a precipitate. Substances which liberate iodine from potassium iodide interfere, for example iron(III) the latter should be reduced with sulphurous acid and the excess of gas boiled off, or by a 30 per cent solution of hypophosphorous acid. Chloride ion reduces the intensity of the bismuth colour. Separation of bismuth from copper can be effected by extraction of the bismuth as dithizonate by treatment in ammoniacal potassium cyanide solution with a 0.1 per cent solution of dithizone in chloroform if lead is present, shaking of the chloroform solution of lead and bismuth dithizonates with a buffer solution of pH 3.4 results in the lead alone passing into the aqueous phase. The bismuth complex is soluble in a pentan-l-ol-ethyl acetate mixture, and this fact can be utilised for the determination in the presence of coloured ions, such as nickel, cobalt, chromium, and uranium. 

Subcategory A encompasses the manufacture of all batteries in which cadmium is the reactive anode material. Cadmium anode batteries currently manufactured are based on nickel-cadmium, silver-cadmium, and mercury-cadmium couples (Table 32.1). The manufacture of cadmium anode batteries uses various raw materials, which comprises cadmium or cadmium salts (mainly nitrates and oxides) to produce cell cathodes nickel powder and either nickel or nickel-plated steel screen to make the electrode support structures nylon and polypropylene, for use in manufacturing the cell separators and either sodium or potassium hydroxide, for use as process chemicals and as the cell electrolyte. Cobalt salts may be added to some electrodes. Batteries of this subcategory are predominantly rechargeable and find application in calculators, cell phones, laptops, and other portable electronic devices, in addition to a variety of industrial applications.1-4 A typical example is the nickel-cadmium battery described below. 

Antimony, arsenic, bismuth, cadmium, calcium, cesium, chromium, cobalt, copper, gold, indium, iridium, iron, lead, lithium, magnesium, manganese, mercury, nickel, palladium, platinum, potassium, rhodium, rubidium, ruthenium, selenium, silver, sodium, tellurium, thallium, zinc... 

Major constituents (greater than 5 mg/L) Minor constituents (O.Ol-lO.Omg/L) Selected trace constituents (less than 0.1 mg/L) Bicarbonate, calcium, carbonic acid, chloride, magnesium, silicon, sodium, sulfate Boron, carbonate, fluoride, iron, nitrate, potassium, strontium Aluminum, arsenic, barium, bromide, cadmium, chromium, cobalt, copper, gold, iodide, lead, Uthium, manganese, molybdenum, nickel, phosphate, radium, selenium, silver, tin, titanium, uranium, vanadium, zinc, zirconium... 

Elemental composition Co 45.39%, Cl 54.61%. Aqueous solution of the salt or acid extract may be analyzed for cobalt by AA, ICP, or other instrumental techniques following appropriate dilution. Chloride anion in the aqueous solution may be measured by titration with silver nitrate using potassium chromate indicator, or by ion chromatography, or chloride ion-selective electrode. 

The vendor claims that the following metals have been successfully treated to parts per biUion (ppb) and detection limit levels aluminum, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel, selenium, silver, tin, uranium, vanadium, and zinc. The system is also able to remove ammonia, nitrates, phosphates, potassium, fluorides, and sodium. Studies have also been performed using Aqua-Fix to remove radionuchdes such as uranium from waste streams. 

The crude substance is their recrystallised from water containing acetic acid. The compound was originally believed to exist in two isomeric forms, but Jorgensen found the crystalline form depends on the concentration of acetic acid used for crystallisation, inasmuch as rhombic leaflets separate from hot dilute acetic acid, and from hot concentrated acid the substance separates in yellow-brown needles. The complex is sparingly soluble in water, and gives no precipitate in aqueous solution with silver nitrate or potassium chromate. If treated with cold hydrochloric acid it is transformed into chloro-dinitro-triammino cobalt, [Co(NH3)3(N02)2Cl], and if warmed with concentrated hydrochloric acid gives diehloro-aquo-triammino-cobaltic chloride. 

Silver(II) fluoride and potassium tetrafluoroargentate(III) have similar reactivities towards benzene,11 and appear to be slightly less reactive than cobalt(III) fluoride a similar range of products is formed. Potassium hexafluoronickelate(IV) is slightly more reactive than cobalt(III) fluoride under vapor-phase conditions18 (sec above for reactions of K2NiF6 in anhyd HF) the products are similar to those from cobalt(III) fluoride except that more unsaturates are detected, mainly the ones that predominated in the manganese(III) fluoride fluorination. 

Many salts of nitraminomethane are known, some of them more or less explosive, eg, ammonium, barium, cobalt, cadmium, copper, nickel, potassium, silver, sodium and zinc (Refs 1,2 3)... 

A disulphide, [(HCS)2S is formed as a yellowish-red precipitate when potassium dithioformate in alcohol solution is cautiously oxidised by the addition of iodine. It decomposes similarly to the acid above 200° C. Both sulphides are insoluble in the common solvents. Dithioformates of silver, lead, zinc and cobalt have also been described.2... 

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