Chromy chloride

When aquo-pentammino-saits lose water the acid residue enters the complex, just as in the ease of loss of ammonia from the complex. For example, aquo-pentammino-chromie chloride, [Cr(NIi3)s(II20)]Cl3, on loss of water becomes ehloro-pentammino-ehromic chloride, [Cr(NH3)5Cl]Cl2. Other aquo-salts behave similarly, and almost any acidic radicle attached to the complex as a whole may in this way be caused to enter the complex itself. 

Aquo-pentammino-chromic Hydroxide, [Cr(NH3)5H20](OH)3, is known only in solution, and is formed when dry chloro-pentammino-chromie chloride, [Cr(NH3)5Cl]Cl2, is rubbed, in absence of light, with moist silver oxide and water on filtering a deep red solution, which is strongly alkaline in reaction, is left, which contains the base, Cr[(NH3)5H20](OH)3. The solution is unstable and decomposes on... 

Indirectly the change from trans- into cis-salt may be brought about by warming irans-dichloro-diethylenediamino-ehromic chloride with ethylenediamine triethylenediamino-chromie chloride is produced, and this on heating to 150° C. loses one molecule of ethylenediamine, giving the violet cw-salt, thus ... 

Chromi-. chromic, chromium(III). -chlorid, n. chromic chloride, chromium(III) chloride, -cyanwasserstoffsaure, /. chromicyanic acid cyanochromic(III) acid. 

Mukherjee studied the gas phase equilibria and the kinetics of the possible chemical reactions in the pack-chromising of iron by the iodide process. One conclusion was that iodine-etching of the iron preceded chromis-ing also, not unexpectedly, the initial rate of chromising was controlled by transport of chromium iodide. Neiri and Vandenbulcke calculated, for the Al-Ni-Cr-Fe system, the partial pressures of chlorides and mixed chlorides in equilibrium with various alloys and phases, and so developed for pack aluminising a model of gaseous transport, solid-state transport, and equilibria at interfaces. 

One of the most gentle methods for the generation of reactive allylmetallic reagents was introduced in 1977 by Hiyama and Nozaki1,2,3,33. By the action of two equivalents of chromi-um(II) chloride on allylic halides in tetrahydrofuran at 0°C in the presence of a carbonyl compound, reductive coupling with the formation of a homoallylic alcohol takes place. 

CAUTION. Ethers that have been stored for long periods, particularly in partly-filled bottles, frequently contain small quantities of highly explosive peroxides. The presence of peroxides may be detected either by the per-chromie acid test of qualitative inorganic analyw (addition of an acidified solution of potassium dichromate) or by the liberation of iodine from acidified potassium iodide solution (compare Section 11,47,2). The peroxides are nonvolatile and may accumulate in the fiask during the distillation of the ether the residue is explosive and may detonate, when distilled, with suffident violence to shatter the apparatus and cause serious personal injury. If peroxides are found, they must first be removed by treatment with acidified ferrous sulphate solution (Section 11,47,2) or with sodium sulphite solution or with stannous chloride solution (Section VI,12). The common extraction solvents diethyl ether and di-t so-propyl ether are particularly prone to the formation of peroxides. 

Chromium(III) chloride at elevated termperatures decomposes to chromi-um(II) chloride and chlorine ... 

Chromium hexacarbonyl is prepared by the reaction of anhydrous chromi-um(lll) chloride with carbon monoxide in the presence of a Grignard reagent. A 60% product yield may be obtained at the carbon monoxide pressures of 35 to 70 atm. Other chromium salts may be used with carbon monoxide and Grignard reagent in the preparation. The compound may also be obtained by the reaction of a chromium salt with carbon monoxide in the presence of magnesium in ether or sodium in diglyme. 

The double compound, [Cr(NH3)6H20][Cr(CN)8], is precipitated from the aquo-pentammino-chloride on addition of potassium chromi-cyanide it separates as a sparingly soluble yellow crystalline powder, and on heating with concentrated hydrochloric acid decomposes with formation of ehloro-pentammino-chloride. The ferricyanide, [Cr(NH3)B H20][Fe(CN)6], is precipitated from a dilute solution of the aquo-pentammino-ehloride on addition of potassium ferricyanide, and crystallises in vellowish-brown prisms. The cobalti-cyanide, [Cr(NH3)5H20] [Co(CN)6], obtained, by the addition of potassium cobalti-cyanide, in yellowish-brown crystals, is isomeric with the chromi-eyanide of aquo-pentammino-cobalt, [Co(NH3)sH20][Cr(CN)6]. 

Tetraquo -dipyridino -chromic Chloride, [Cr py2(H20)4]Cl3. 2H2Q,8 formed by acting upon dihydroxo-diaquo-dipyridino-chromie... 

The bromide, [Cr2(NH3)10(OH)]Br5.H2O, may be obtained from the chloride by treating with hydrobromic acid or by heating erythro-chromie bromide to 100° C. The corresponding base of the series is formed in solution when the chloride is treated with moist silver oxide. A blue alkaline liquid is obtained, which soon becomes red and passes into the erythro-hydroxide. 

Chromic bromide reacts in the same way, yielding the dibromo-tetraquo-chromie salt, [Co(NH3)2(N02) J[C r(H2d).1Br2].2H20, and hex-ammino-cobaltic chloride forms the double salt, [Co(NH,)2(XOs)4]8 [Co(XH8)8]., ... 

Cement, laboratory, 189 Cerium amalgam, 15 Cesium, metallic, 79 Chloroamine, 59 Chlorides, anhydrous, 28, 29 of silicon, 42 Chloroplumbic acid, 48 Chromi-oxalates, 37 Chromous acetate, 122 Chromous chloride, 124, 125 solution, 124 tetrahydrate, 126 trihydrate, 126 Cinnabar, 20 Cobalti-oxalates, 37... 

Protection of aldoses at the non-anomeric positions makes it possible to use many of the common procedures in organic chemistry for oxidizing lactols as shown with mannofura-nose 1 and glucopyranose 3 (O Table 1). The reactions can be divided into three main categories oxidations mediated by activated dimethyl sulfoxide (DMSO), oxidations with chromi-um(VI) oxides, and oxidations catalyzed by ruthenium oxides. The DMSO-mediated oxidations of alcohols can be promoted by several activators [27]. With the partially protected aldoses the activation has mainly been achieved with acetic anhydride and oxalyl chloride. Competing /3-elimination does usually not occur unless the eliminating group is an ester, e. g., an acetate or a benzoate [27]. 

Chromy 1 chloride Organic solvents Dioxygen difluoride Various materials Fluorine nitrate Organic materials... 

See Halogens, or Interhalogens, above Chromy 1 chloride Organic solvents Fluorine nitrate Organic materials Hydrogen peroxide Diethyl ether lodine(Vll) oxide Diethyl ether Lithium perchlorate Diethyl ether Nitric acid Diethyl ether Nitrosyl perchlorate Organic materials Nitryl perchlorate Organic solvents Ozone Diethyl ether... 

For this reason it is advisable to prepare chromi-um(II) chloride solution in a weak acid solution (e.g., acetic acid). 

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