Silver compounds Sodium salts

As expected for a tricyano compound, it is highly endothermic (AH°j (s) +348.1 kJ/mol, 3.78 kJ/g), so its stability seems dubious [1]. However, because of isomerisation to the acidic dicyano-enimine (NC)2C=C=NH, it is considerably stabilised and the silver and sodium salts surprisingly are described as stable [2],... 

A solid that contains cations and anions in balanced whole-number ratios is called an ionic compound. Sodium chloride, commonly known as table salt, is a simple example. Sodium chloride can form through the vigorous chemical reaction of elemental sodium and elemental chlorine. The appearance and composition of these substances are very different, as Figure 2-24 shows. Sodium is a soft, silver-colored metal that is an array of Na atoms packed closely together. Chlorine is a faintly yellow-green toxic gas made up of diatomic, neutral CI2 molecules. When these two elements react, they form colorless ciystals of NaCl that contain Na and Cl" ions in a 1 1 ratio. 

For analysis, a silver-containing solution was made alkaline with 25% sodium hydroxide solution and filtered, then the precipitate was washed with ammonium hydroxide to redissolve the silver. Hydrazine (as sulfate) was added to precipitate the silver, and when the mixture was heated, an explosion occurred. This could have been caused by precipitation of explosive silver nitride, rapid catalytic decomposition by silver compounds of the hydrazine salt, and/or ignition of the hydrogen evolved. 

Oxidation of one molar proportion with sodium pieriodate produces two equivalents of formic acid, in accordance with the existence of hydroxyl groups attached to four contiguous carbon atoms. This oxidation (and also that carried out with lead tetraacetate) gives an aldehyde, whose semicar-bazone has an analysis corresponding to that of the semicarbazone of an ethyl formyl-methyl-furoate (XII). By oxidation of aldehyde XII with silver oxide in alkaline solution, 2-methyl-3,4-furandicarboxylic acid (XIV) was obtained this was identical with the compound described by Alder and Rickert.20 The identity was confirmed by preparation of the respective dianilides. The acid XIV has also been prepared by the reaction between the sodium salt of ethyl acetoacetate and ethyl bromopyruvate.9... 

Basic Silver Metavanadate, SAg20.2V205 or Ag20.4AgV03, is prepared by the action of silver nitrate on the corresponding sodium salt. It is a dark yellow compound, almost insoluble in water.8... 

Salts therefore, are prepared (1) from solutions of acids and bases by neutralization and separation by evaporation and crystallization (2) from solutions of two salts by precipitation where the solubility of the salt formed is slight (e.g., silver nitrate solution plus sodium chloride solution yields silver chloride precipitate [almost all as sulid], and sodium nitrate present in solution as sodium cations and nitrate anions [recoverable as sodium nitrate, solid by separation of silver chlondc and subsequent evaporation of the solution]) (3) from fusion of a basic oxide (or its suitable compound—sodium carbonate above) and an acidic oxide (or its suitable compound—ammonium phosphate), since ammonium and hydroxyl are volatilized as ammonia and water. Thus, sodium ammonium hydrogen phosphate... 

Though explosive, it (and its ammonium salt) are much less sensitive to impact or friction than its sodium or potassium salts [1]. A small sample of the latter exploded violently during vacuum filtration. The parent compound explodes spontaneously even in acetone (but not in ethanol or aqueous) solution if traces of acetic acid are present [2], The salts are readily formed from diaminoguanidine salts and alkali nitrites. The ammonium salt explodes on heating, and the silver salt is violently explosive even when wet [1]. The sodium salt is also readily formed from cyanogen azide. 

The acid is soluble in hot water and the usual solvents, insoluble in ether. Its diazo-compound is citron-yellow and gives a red dye with alkaline resorcinol. The sodium salt forms glistening groups of silver crystals containing 5 molecules of water. en carbonyl chloride is passed into a solution of tlie arsinic acid in aqueous sodium acetate, a white crystalline product is obtained. ... 

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