Cerous hydroxide

Hydroxide. Freshly precipitated cerous hydroxide [15785-09-8] Ce(OH)2, is readily oxidized by air or oxygenated water, through poorly defined violet-tinged mixed valence intermediates, to the tetravalent buff colored ceric hydroxide [12014-56-17, Ce(OH)4. The precipitate, which can prove difficult to filter, is amorphous and on drying converts to hydrated ceric oxide, Ce02 2H20. This commercial material, cerium hydrate [23322-64-7] behaves essentially as a reactive cerium oxide. 

Cerous carbonate octahydrate, 5 676 Cerous carbonate trihydrate, 5 676 Cerous chloride hydrate, 5 676 Cerous fluoride, 5 676 Cerous hydroxide, 5 676 Cerous oxalate, 5 676 Cerous oxychloride, 5 676 Cerous oxyfluoride, 5 676 CerOx Corporation electrolysis cells, 9 669-670... 

Reactions with caustic alkahs yield cerous hydroxide ... 

Synonyms cerous hydroxide cerium hydroxide cerous hydrate Uses... 

Ending formerly added to stems of element names to indicate a lower oxidation state, e.g. ferrous chloride, cuprous oxide, cerous hydroxide. Such names are no longer acceptable. 

Catechol, 47, 60, 120, 128, 451, 467-A68, 837, 857, 1011-1012 carbonate, 119-120 dibenzenesulfonate, 47 dichloromethylene ether, 119-120 Catechyl phosphorus trichloride, 120 Cathyl chloride (Ethyl chloroformate), 86, 239, 363, 364-367 Cedrol.913 Cdite, 120 Cellobiose, 893 o-Cellobiose oclaacetate, 158 Cfmulsol, 820 o-Cephalins, 847 Ceric acetate, 1062 Ceric ammonium nitrate, 120-121 Cerous chloride, 121 Cerous hydroxide, 121 Cesium fluoride, 117,121, 933 Cetyl alcohol, 497, 862 Cetyl iodide, 497, 862, 1279 Cetyltrimethylamroonium horohydride, 1143 Cetyltrimelhylaromonium bromide, 121-122 Cevadine, 798 Ovine, 59... 

Ceric hydroxide, Ce(OH)4, is not known. A hydrated oxide, probably Ce20(0H)6, forms as a yellow gelatinous precipitate when ammonia or an alkali hydroxide is added to a ceric salt. It may also be prepared by the oxidation of cerous hydroxide. It dissolves in nitric acid, forming a ceric salt, in sulfuric acid yielding a partially reduced product, and in hydrochloric acid giving cerous chloride and chlorine. 

Ceric sulfate, Ce(S04)2-4 H20 [1, 121, before Cerous hydroxide]. Mol. wt. 404.32. Suppliers Riedel-de Haen, Alfa Inorganics. 

In the hydrolysis of the latter compound, Sarin, catalysis by cerous, cupric, and manganous ions in the form of bifunctional species which have a nucleophilic center (hydroxide ion) and an electrophilic center (M+) was particularly effective (19). Although the hydroxometallic ions are considerably weaker bases than hydroxide ion itself, they are catalytically more active by a factor of 10. This activity can be explained by the bifunctionality of these compounds mentioned above. 

Calcium Peroxide 1305-79-9 Cerous Chloride 7790-86-5 Chromic Hydroxide 1308-14-1... 

Iron-gray, ductile, malleable metal face -cen tered cubic structure at room temp. Stable in dry air, but superficially oxidized in moist air when finely divided may ignite sponta -neously. d 6.77. mp 795". E (aq) Cei+ /Ce — 2,48 V (calc). Slowly dec by cold, rapidly by hot water sol in dil mineral adds. Ceric salts usually are yellow to orange-red in color tnd liberate iodine from KI. Cerous salts are usually white tnd give a white ppt with alkali hydroxides or sulfides, insol ineicess of reagent they also are pptd by ammonium oxalate from cold dil acid sols. 

An alternative American process uses a feed produced by oxalate precipitation of thorium and rare earths. This precipitate is calcined to the oxides and dissolved in nitric acid for extraction with undiluted TBP. After stripping with 8N nitric acid, a high proportion of cerium extracts with the thorium, but the other rare earths are eliminated. The cerium is then back-washed in a separate extractor by means of 0 1 N sodium nitrite solution, which reduces it to the solvent-insoluble cerous condition. Thorium is then backwashed in the last extractor with either water or 2 per cent sulphuric acid. In order to make this process economic it was necessary to devise an efficient system of oxalic acid recovery. This was based upon treatment of the thorium and rare earth oxalates with sodium hydroxide and recycling the resulting sodium oxalate to the precipitation stage. 

The test is not directly applicable in the presence of manganese, cobalt, copper, silver, thallium, or chromates because they, too, oxidize benzidine. In these instances it is advisable to precipitate cerous fluoride from the neutral or slighly acid test solution with hydrofluoric acid, then to produce Ce ii hydroxide by spotting with alkali, and apply the benzidine test. 

The hydroxide Ce(OH)4 precipitates at pH values about 1 in sulfuric acid solution. The cerous ion Ce + precipitates as hydroxide Ce(OH)3 at about pH = 7.5. 

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