Nitric acid equivalent weight

A weight of compound, containing about 0-05 g. of fluorine, was dissolved in 10 ml. of dry alcohol and metallic sodium (about 0 5 g., i.e. at least 5 equivalents) was added. After the sodium had dissolved, the mixture was gently heated under reflux for 5 min.,8 and then washed out with about 100 ml. of water into a beaker, made acid to bromophenol blue with dilute nitric acid and then just alkaline with 10 per cent sodium hydroxide solution. Three ml. of 10 per cent sodium chloride solution were added and the solution was diluted to 250 ml. One ml. of concentrated hydrochloric acid was added, and the solution heated on a water-bath to about 80°. Then 5-0 g. of finely powdered A.R. lead nitrate were added with stirring (still at 80°). As soon as all the lead nitrate had dissolved, 5-0 g. of crystalline sodium acetate were added, with vigorous stirring. The product was then heated on the water-bath for 15 min. and cooled in ice, and the precipitate was filtered off on a Swedish filter paper. It was washed once with water, four times with saturated PbClF solution... 

Arfwedson prepared lithium acetate, ignited it, and noted the insolubility of the resulting lithium carbonate in water and its action on platinum. He also prepared and studied the bicarbonate, sulfate, nitrate, chloride, tartrate, borate, hydroxide, and a double sulfate which he reported as lithium alum. He mentioned that lithium hydroxide is much less soluble than the other caustic alkalies and that it has a greater saturation capacity [lower equivalent weight] than they. Because of its ability to form deliquescent salts with nitric and hydrochloric acids, Arfwedson recognized the close relation between the new alkali and the alkaline earths, especially magnesia. 

The Russian process uses only a 25 per cent excess of caldum but also a quantity of caldum chloride is adddl to the readants, equivalent to 40 per cent of the weight of the thorium oxide. Leaching is with hydrochloric add, but this is followed by a polishing operation with 15 per cent nitric acid before washing and drying. 

For assay determine the weight of injection in a sufficient number of containers and dissolve in a sufficient quantity of concentrated nitric acid. Evaporate to dryness, moisten the residue with concentrated sulphuric acid and ignite at a temperature not exceeding 500°. Dissolve the residue in just sufficient concentrated nitric acid to prevent precipitation of the metal when the solution is diluted to a suitable volume with water. Using a volume of the resulting solution equivalent to about 2 g of the sample, complete as in the general method for determination of bismuth given above, p. 127. 

In extending this mode of no tation to salts and compound aethers, we must of course keep carefully in view the capacity of saturation of their acids, writing the monobasic acids as hydrochloric, nitric, acetic, c. at half their usual equivalents, CIH, NO H, Q2 O, but retaining the customary atomic weights of the bibasic acids, as sulphuric, carbonic, oxalic, c. 

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