Manual of Qualitative Chemical Analysis. (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1866. Excerpt: ... upon ebullition or upon mixing the solution with alcohol; the latter agent serves also to effect the separation of malate of lime from aqueous solutions. If, therefore, we add to our fluid, --3. Chloride of Calcium and Chloride of Ammonium, Oxalic Acid, Paratartaric Acid, and Taetaric Acid are precipitated, but the lime-salts of several inorganic acids, which have not yet been separated, phosphate of lime, for instance, precipitate along with them. We must therefore select for the individual detection of the precipitated organic acids such reactions only as preclude the possibility of confounding the organic acids with the inorganic acids that have been thrown down along with them. For the detection of oxalic acid we select accordingly solution of sulphate of lime, with addition of acetic acid ( 148); to effect the detection of the tartaric and paratartaric acids, we treat the precipitate produced by chloride of calcium with solution of soda, since the limesalts of these two acids only are soluble in this menstruum in the cold, but insoluble upon ebullition. Of the organic acids we have now still in solution citric acid and malic acid, succinic acid and benzoic acid, acetic acid and formic acid. Citric Acid and Malic Acid precipitate upon addition of alcohol to the fluid filtered from the oxalate, tartrate, &c, of lime, and which still contains an excess of chloride of calcium. Sulphate and borate of lime invariably precipitate along with the malate and citrate of lime, if sulphuric acid and boracic acid happen to be present; the analyst must therefore, carefully guard against confounding the lime precipitates of these acids with those of citric acid and malic acid. The alcohol is now removed by evaporation, and to the perfectly neutral solution, --4....