Tin oxide SnO

Tin ll) oxides. Lower tin oxides SnO (white, NH4OH to SnCli solution black, heat on white SnO red), form a complex system. 

The solubility of catalyst was also a key feature in these reactions for instance, the solid tin oxides (SnO and Sn02) were equally inactive on the oleic acid esterification with ethyl alcohol, certainly, due to its almost complete insolubility (Figure 12). 

Baker et al. (2006) have shown that small amounts of gold (9.4 wt%) deposited on powder of hydrated tin oxide (SnO) make a good catalyst for four-electron oxygen reduction in acidic and alkaline solntions. 

The precipitate obtained is in fact colloidal and has no definite composition. Careful drying of the precipitate gives the anhydrous oxide, SnO, which may also be prepared by heating tin(II) ethane-dioate (oxalate) ... 

Tin(II) oxide is a dark-coloured powder which oxidises spontaneously in air with the evolution of heat to give tin(IV) oxide, SnO, ... 

Stannous Oxide. Stannous oxide, SnO ((tin(II) oxide), mol wt 134.70, sp gr 6.5) is a stable, blue-black, crystalline product that decomposes at above 385°C. It is insoluble in water or methanol, but is readily soluble in acids and concentrated alkaHes. It is generally prepared from the precipitation of a stannous oxide hydrate from a solution of stannous chloride with alkaH. Treatment at controUed pH in water near the boiling point converts the hydrate to the oxide. Stannous oxide reacts readily with organic acids and mineral acids, which accounts and for its primary use as an intermediate in the manufacture of other tin compounds. Minor uses of stannous oxide are in the preparation of gold—tin and copper—tin mby glass. 

The corrosion of tin in various atmospheres has been extensively monitored recently using XPS and AES techniques ". While it is difficult to resolve the peaks from the tin oxides and establish their degree of surface hydration, there is general agreement that both SnO and SnOj may be present depending on the temperature of exposure to oxygen. 

Many metallic elements in the p and d blocks, have atoms that can lose a variable number of electrons. As we saw in Section 1.19, the inert-pair effect implies that the elements listed in Fig. 1.57 can lose either their valence p-electrons alone or all their valence p- and s-electrons. These elements and the d-block metals can form different compounds, such as tin(II) oxide, SnO, and tin(IV) oxide, Sn02, for tin. The ability of an element to form ions with different charges is called variable valence. 

Stripping of chlorine from hydroxides such as Cl2Sn(OH)2 could eventually lead to gas-phase SnO or Sn02. However, at the relatively low temperatures typical of tin oxide CVD ( 873-973 K), we do not expect these oxides to form, based on the equilibrium calculations described above. Thus, the formation of tin hydroxides is not only thermodynamically favored (i.e., based on minimization of the Gibbs free energy), but there are also exothermic reaction pathways that we expect to be kinetically favorable. The primary tin carrier in the CVD process could therefore be a tin hydroxide. Complete conversion to Sn02 would most likely occur via reactions on the surface. 

Sodium cyanide solution dissolves certain metals (I) with absorption of oxygen, e.g.. gold, silver, mercury, lead, and (2) with evolution of hydrogen, e.g.. copper, nickel, iron. zinc, aluminum, magnesium and solid sodium cyanide, when heated with certain oxides, e.g.. lead monoxide PhO. stannic oxide SnO.. yields the metal of the oxide, e.g.. lead. tin. respectively. and sodium cyanate NaCNO. Two classes of esters arc known, cyanides or nitriles, and isocyanides, isonitriles or carbylatnincs. the latter being very poisonous and of marked nauseating odor... 

Tin forms two series of compounds tin(II) or stannous compounds and tint IV1 or stannic compounds. Tin(ll) oxide, SnO, insoluble in water, is formed by precipitation of an SnO hydrate from an S11CL solution with alkali and later treatment in water (near the boiling point and at constant pH). It is amphiprotic, but only slightly acid, forming stannites slowly with strong alkalis. Sodium stannite is conveniently prepared from... 

There are two series of compounds of tin and the halogens those related to stannous oxide, SnO, in which the metal has a valence of 2 (stannous salts), and those related to stannic oxide, Sn02, in which it has a valence of 4 (stannic salts). The compounds with lower valence are usually prepared by the action of the halogen acids on the metal. Stannous chloride, for example, is formed when hydrochloric acid reacts with tin. Stannic salts, on the other hand, are prepared by the reaction of tin and the free halogen. In this preparation stannic bromide results from the reaction of bromine and tin. The reaction between the two ele-... 

Amphoteric oxides are capable of functioning either as acidic or as basic oxides. Thus tin dioxide, SnO, functions as a basic oxide in stannic sulphate, Sn(S04)2, but as an acidic oxide m sodium a stannate, Na2Sn03. Lead dioxide yields the tetrachloride, PbCl4, and sodium metaplumbate, Na2Pb03, respectively Similarly aluminium oxide, Al2Os, yields the trichloride, AlCla, and the alummate Na2AI204. 

Commercial production of stannous fluoride is carried out by a reaction between mossy tin and anhydrous HF. It is also prepared by dissolving stannous oxide, SnO, in aqueous HF. 

The specific systems selected for this study are described later. The major problem of TCO is the first irreversible capacity loss, resulting from the reaction of lithium with SnO and the formation of Li20. Nevertheless, the development of TCO was the first demonstration of the potential for creating the so-called active-inactive nanocomposite anode materials by the electrochemical insertion of lithium into the tin oxide-based amorphous glass. 

Stannylsulfonamides can also be prepared by the addition of the SnO bond to sulfo-diimides (RN=S=NR) or sulfinylamines (RN=S=0) in these reactions, the bis(trialkyl-tin) oxides appear to be more reactive than the corresponding alkoxides.62-63 The weak sulfur-containing acceptors can then be displaced by more powerful acceptors such as isocyanates or chloral. 

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