Silver suboxide

Silber-oxydul, n. silver suboxide, -ojydver bindung,/. compound of silver oxide specif., argentate. -papier, n. silver paper, silvered paper. 

Synonyms silver peroxide argentic oxide silver suboxide Divasil... 

When heated, the salt first melts and at a higher temperature it decomposes to form silver 7 reduction to the metal occurs more readily when heated with carbon.8 Partial reduction also occurs when the orthoarsenate is treated with formaldehyde 9 or with ferrous sulphate solution 10 in the former ease silver is formed, but in the latter silver suboxide. 

Silver hyponitrite is bright yellow, and if pale in colour it generally contains a trace of ammonia, or some silver oxide. If black silver suboxide is present, the colour may be greyish-yellow, and with other impurities present, the colour may be bright green. There is no evidence that the difference in colour is due to the presence of allotropic forms. When precipitated from strongly alkaline soln., or from cone. soln. of the sodium and silver salts, the precipitate is compact, and dense, but if precipitated from dil. soln., it is flocculent and bulky. A. Kirschner, and C. Paal and F. Kretschmer, obtained crystals of silver hyponitrite by deposition from the ammoniacal soln., either by evaporation or by dilution with water. 

Silver (II) oxide Argentic oxide silver peroxide silver suboxide di vsai1 No data AgO... 

Silver suboxide, Ag40.—Several experimenters have described the formation of a suboxide by reduction of silver compounds, but the subject seems to merit further investigation. Silver subfluoride is said to react with water-vapour at 180° C., yielding a black powder of the... 

The monoxide is decomposed by heat into silver and oxygen, the liberated metal playing the part of an autocatalyst in accelerating the reaction.5 Finely divided platinum and manganese dioxide also cause acceleration of the transformation. It is decomposed by the action of light, with evolution of oxygen, and possibly formation of silver suboxide. 

Wohler obtained phosphorus by strongly heating a mixture of sand and bone-black (calcium phosphate and carbon) — the modern process, now carried out in the electric furnace. He prepared artificial nickel arsenide and worked on the separation of iridium and osmium in a pound of platinum residues given him by Dumas on a visit to Paris in 1833. A supposed silver suboxide, Ag40, prepared by Wohler by the action of caustic potash solution on a supposed subcitrate made by heating silver citrate in hydrogen at 100°, was not analysed and was probably a mixture of silver and silver oxide AggO the red colour of the solution of the subcitrate was probably due to colloidal silver. ... 

Combinations op Silver.—There are three oxides of silver—a suboxide, a protoxide, and a bin oxide. Of these the protoxide alone forms permanent and definite saline combinations. 

Silver subfluoride, Ag2F.—When a saturated solutidn of silver fluoride is heated with finely divided silver, a golden-yellow, crystalline precipitate of the composition Ag2F is produced.11 The reaction is attended by the evolution of 0-7 Cfal.,12 and the heat of formation of the subfluoride from its elements is 26-3 Cal. At 180° C. water-vapour converts the fluoride into the suboxide, Ag40.13... 

Silver monoxide dissolves in water, forming an alkaline solution which turns red litmus blue. At 25° C. its solubility corresponds with 2-16 xlO-4 gram-molecule per litre of water,6 and at 15° C. Rebi re 7 found the same value. It is a strong base, its salts having a neutral reaction. The solution is coloured reddish and decomposed by the action of light, the change being possibly attended by deposition of the suboxide or of colloidal silver. 

Indeed, it has been demonstrated 88) that Cs suboxides are of essential importance in the famous infrared sensitive SI photocathode 89). These cathodes contain a thin layer of oxidized Cs on a silver substrate. It is evident from UPS measurements on such a cathode prepared in a PE spectrometer that the Cs—0 layer is essentially composed of Csj 1O3, or a higher oxidized, but still metallic suboxide, giving rise to the characteristic spectrum of the bulk material, although the layer has only the thickness of a few atoms. 88) The high yield of photoelectrons in the near infrared with the SI photocathode results from two effects CS11O3 is characterized by a sufficiently small work function (emit photoelectrons when irradiated with infrared light. Furthermore, the energy necessary to create surface plasmons... 

The reduction of metallic salts provides a convenient test for reducing sugars. In alkaline solution, the sugars reduce the salts of copper, silver, mercury, and other metals to the metal or to a suboxide. The well-known Fehling and Tollens solutions are of this character. The sugar and some of the products resulting from isomerization in alkaline solution (see Chapter I) are oxidized to the corresponding acids. The formation of the metal or... 

The fact that we can write a formula for a compound from the valences of the constituent atoms does not mean the compound must exist. We can write AgOH for the compound silver hydroxide, but no compound of this definite composition has yet been isolated. Conversely, many compounds exist whose formulas cannot be deduced by this scheme examples are benzene, CgHe, and carbon suboxide, C Oa. 

Dimethylketene has beep obtained in unspecified yield by heating the monochloride of dimethylmalonic acid it is probable that the malonic anhydride was formed as an intermediate. This method failed in attempted applications to diethylketene, and carbon suboxide. Low yields of carbon suboxide have been obtained by tteating malonyl chloride with lead, silver, or zinc oxide or with silver oxalate or malonate, and by treating silver malonate with cinnamoyl chloride malonic anhydrides or mixed anhydrides may be intermediates. 

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