THE INFLUENCE OF LEAD ON THE FERROCYANIDE TITRATION OF ZINC

Victor. Lenher, C. C. Meloche
1913 Journal of the American Chemical Society  
In weak solutions with ferric chloride neither a-oxan, nor p-oxan salts give a precipitate. Cakium salts both of a-oxan and of p-oxan are amorphous, gelatinous substances. Compared with' calcium carbonate they are much more soluble in water (up to I gram to a liter). The sodium salt of a-oxan like sodium carbonate forms with manganous chloride (MnClJ an abundant white precipitate, while under the same conditions the sodium salt of /3-oxan gives no precipitate. Aluminium chloride acts in the
more » ... ide acts in the same manner with the difference that the precipitates formed from sodium carbonate and sodium a-oxanate salts, decompwe with elimination of gases; but the sodium salt of ilj-oxan under the same conditions and a t the same dilution (2.5 grams to 2 5 0 cc. of water) does not give a precipitate and does not eliminate gas. Both the salts of aoxan and the salts of p-oxan in time lose, in a larger or smaller degree, the property of eliminating gas, or in other words the quantity of gas eliminated diminishes. This fact is more sharply pronounced in /?-oxan salts. This property is most probably due to polymerization and may be dependent upon the presence of certain admixtures acting as catalyzers, for in certain cases it is more pronounced than in others.
doi:10.1021/ja02191a004 fatcat:qompxyldrbbt7au7nbtpvutu5e