Silver , oxidation

The conversion of primary alcohols and aldehydes into carboxylic acids is generally possible with all strong oxidants. Silver(II) oxide in THF/water is particularly useful as a neutral oxidant (E.J. Corey, 1968 A). The direct conversion of primary alcohols into carboxylic esters is achieved with MnOj in the presence of hydrogen cyanide and alcohols (E.J. Corey, 1968 A,D). The remarkably smooth oxidation of ethers to esters by ruthenium tetroxide has been employed quite often (D.G. Lee, 1973). Dibutyl ether affords butyl butanoate, and tetra-hydrofuran yields butyrolactone almost quantitatively. More complex educts also give acceptable yields (M.E. Wolff, 1963). 

The halide anion of quaternary ammonium iodides may be replaced by hydroxide by treatment with an aqueous slurry of silver oxide Silver iodide precipitates and a solu tion of the quaternary ammonium hydroxide is formed... 

Nitrobenzene Nitric acid, nitrous oxide, silver perchlorate... 

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

Silver sulfate decomposes above 1085°C into silver, sulfur dioxide, and oxygen. This property is utilized ia the separation of silver from sulfide ores by direct oxidation. Silver sulfate is reduced to silver metal by hydrogen, carbon, carbon monoxide, zinc, and copper. 

Silver(II) Oxide. Silver(II) oxide [1301 -96-8, 35366-11-1], AgO, is prepared by persulfate oxidation of Ag20 in basic medium at 90°C or by the... 

Fire Hazards - Flash Point Not flammable Flammable Limits in Air (%) Not flammable Fire Extinguishing Agents Not pertinent Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Not pertinent Behavior in Fire Decomposes to silver oxide, silver, and carbon dioxide. The reaction is non violent Ignition Temperature Not pertinent Electrical Hazard Not pertinent Burning Rate Not pertinent. 

Answer the following questions and, for each yes response, write a balanced cell reaction and calculate the standard cell emf. (a) Can the oxygen present in air oxidize silver metal in acidic solution (b) Can the oxygen in air oxidize silver metal in basic solution ... 

Silver bromide Silver chloride Silver perchlorate Silver cyanide Silver fluoride Silver iodide Silver permar>gate Silver nitrate Silver carbonate Silver oxide Silver sulphate Silver sulphide Silver phosphate... 

Promoters may influence selectivity by poisoning undesired reactions or by increasing the rates of desired intermediate reactions so as to increase the yield of the desired product. If they act in the first sense, they are sometimes referred to as inhibitors. An example of this type of action involves the addition of halogen compounds to the catalyst used for oxidizing ethylene to ethylene oxide (silver supported on alumina). The halogens prevent complete oxidation of the ethylene to carbon dioxide and water, thus permitting the use of this catalyst for industrial purposes. 

See other metal oxides, silver compounds 0037. Silver peroxochromate... 

Hydrogen sulfide is rapidly oxidised, and may ignite in contact with a range of metal oxides, including barium peroxide, chromium trioxide, copper oxide, lead dioxide, manganese dioxide, nickel oxide, silver(I) oxide, silver(II) oxide, sodium peroxide, and thallium(III) oxide. In the presence of air, contact with mixtures of calcium oxide or barium oxide with mercury oxide or nickel oxide may cause vivid incandescence or explosion. 

Catalyst, alumina, 34, 79 35, 73 ammonium acetate, 31, 25, 27 copper chromite, 31, 32 36, 12 cuprous oxide-silver oxide, 36, 36, 37 ferric nitrate, hydrated, 31, 53 piperidine, 31, 35 piperidine acetate, 31, 57 Raney nickel, 36, 21 sulfuric acid, 34, 26 Catechol, 33, 74 Cetylmalonic acid, 34, 16 Cetylmalonic ester, 34,13 Chlorination, by sulfuryl chloride, 33, 45 ... 

Creosol, 33, 17 Crotonaldehyde, 33, IS 34, 29 diethyl acetal, 32, 5 Cupric acetate monohydrate, 36, 77 Cuprous oxide-silver oxide, 36, 36, 37 Cyanamide, 34, 67 36, 8 Cyanoacetamide, 32, 34 Cyanoacetic acid, 31, 25 Cyanoacetylurea, 37, 16 >-Cyanobenzaldehyde, 30, 100 >-Cyanobenzaldiacetate, 36, 59 3-Cyano-5,6-dimethyl-2(l)-pyridone, 32,34 N-2-Cyanoethylaniline, 36, 6 N-2-Cyanoethyl- -anisidine, 36, 7 Cyanoethylation, of aniline, 36, 6 of ethyl phenylcyanoacetate, 30, 80 N-2-Cyanoethyl-m-chloroaniline, 36, 7 Cyanogen, 32, 31 Cyanogen iodide, 32, 29 Cyanogen iodide, complex with sodium iodide, 32, 31... 

Nitrites Nitrobenzene Nitroethane Nitrogen trichloride Organic nitrites in contact with ammonium salts, cyanides Nitric acid, nitrous oxide, silver perchlorate Hydroxides, hydrocarbons, metal oxides Ammonia, As, hydrogen sulfide, nitrogen dioxide, organic matter, ozone, phosphine, phosphorus, KCN, KOH, Se, dibutyl ether... 

While it feels as though all the mouth fills with this pain, in fact the pain only manifests itself through those teeth filled with metal, the metal being silver dissolved in mercury to form a solid - we call it a silver amalgam. Corrosion of the filling s surface causes it to bear a layer of oxidized silver, so the tooth filling also represents a redox couple, with silver and silver oxide coexisting. 

Silver(l) oxide Silver oxide (8) Silver oxide (Ag20) (9) (20667-12-3) Triphenylarsine Arsine, triphenyl- (8,9) (603-32-7)... 

Ethylene oxidation to ethylene oxide. Silver catalyst placed in the pores of the tube (8wt% Ag). 

Diazirines have been prepared by dehydrogenation of diaziri-dines with mercuric oxide, silver oxide, or dichromate-sulfuric acid. The present procedure corresponds to that of Schmitz and Ohme. The procedure for the preparation of the 3,3-penta-methylenediaziridine has been reported by H. J. Abendroth. ... 

In the 1940s and 1950s, a considerable amount of research was funded to find and develop the chemists impossible dream a process for the direct oxidation of ethylene to EO, without any by-products. Finally, Union Carbide found the silver bullet that did the joE)—a catalyst made of silver oxide. Silver oxide is the only substance found having sufficient activity and selectivity. (Activity relates to the amount of conversion, selectivity relates to the right yield.) Moreover, ethylene is the only olefin affected in this way. The others, propylene, butylene, etc., tend to oxidize completely, forming carbon dioxide and water. But when silver oxide is used as a catalyst with ethylene, the dominant reaction is the formation of EO. Some ethylene still ends up being further oxidized, as much as 25% in some processes, as shown in Figure 10—2. 

Aromatic cation-radicals can also react with NOj", giving nitro compounds. Such reactions proceed either with a preliminary prepared cation-radical or starting from nncharged componnd if iodine and silver nitrite are added. As for mechanisms, two of them seem feasible—first, single electron transfer from the nitrite ion to a cation-radical and second, nitration of ArH with the NOj radical. This radical is quantitatively formed when iodine oxidizes silver nitrite in carbon tetrachloride (Neelmeyer 1904). 

Partial oxidation of 158 by bromine yields bromine-free 159 together with mono-, di-, and tribromo derivatives. Other useful reagents are nitrous acid (54JCS286) or the one-electron oxidants silver acetate (in substoichio-metric quantity) and cerium(IV) ammonium nitrate (only for the methyl ether of 158 86BCJ511). 

Compounds Silver nitrate silver chloride silver oxide silver sulfide... 

Synonyms silver peroxide argentic oxide silver suboxide Divasil... 

Rh (NHo) 5C1] (OH) 2, is produced by mixing the chloride with moist silver oxide. Silver chloride is precipitated, and a strongly alkaline liquid produced containing the hydroxide. The base absorbs carbon dioxide from the air, removes ammonia from ammonium salts, and precipitates metallic hydroxides from solutions of the metallic salts. It is only known in solution, and on evaporation of the liquid it is slowly transformed in the cold, more rapidly on heating, into a mixture of aquo-pentammino-rhodium chloride and aquo-pentammino-rhodium hydroxide, thus ... 

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