Lead acetate sugar

Synonyms lead(II) acetate plumbous acetate normal lead acetate neutral lead acetate sugar of lead... 

Lead Acetate (Sugar of Lead or Plumbous Acetate)(Bleiazetat or Bleizucker in Ger), Pb(CH,COO),. 3II1O, mw 379.35. Wh monocl Cfysts, d 2.55, mp- loses 311 0 at 75° for the anhyd salt, Pb(CHjCOO), mw 325.35 mp ca 280°. Sol in w and glycerin si sol in ale, chlf, CCl benz. Can be prepd by dissolving litharge in hot coned AcOH or by treating a mixt of lead and AcOH with air under press. Its lab method of prepn from red lead oxide (Pb O,), AcOH and chlorine is described in Ref 2... 

Synonyms.— Lead Acetate Sugar of Lead. Composition.—Pb(C2H802)2.3Aq. 

Lead formate is only slightly soluble in cold water, and insoluble in hot absolute ethanol it can therefore be readily distinguished from lead acetate or sugar of lead because, quite apart from chemical tests, the acetate is readily soluble in cold water and moderately soluble in ethanol. 

Acetone was originally observed about 1595 as a product of the distillation of sugar of lead (lead acetate). In the nineteenth century it was obtained by the destmctive distillation of metal acetates, wood, and carbohydrates with lime, and pyrolysis of citric acid. Its composition was determined by Liebig and Dumas in 1832. 

Basic Lead Acetate. Basic lead acetate [1335-32-6] (lead subacetate), 2Pb(0H)2-Pb(C2H3 02 )2, is a heavy white powder which is used for sugar analyses. Some physical properties are given in Table 4. Reagent grade is available in 11.3-kg cartons and in 45- and 147-kg fiber dmms. 

Chemical Designations - Syiwnyms Lead acetate trihydrate Neutral lead acetate Normal lead acetate Salt of Saturn Sugar of lead Chemical Formula Pb(C2H30i)2-3H20. 

Heat a small part of the crystals in a dry test tube, first carefully, and then more strongly (280 °C). What happens to the lead acetate in the air and when heated Can lead sugar be dried in a desiccator over sulphuric acid ... 

Lead Acetates (Basic) are obtained by dissolving lead oxide in aq solns of sugar of lead, white solids, very sol in w. Ullmann (Ref 2) gives their formulae as, [Pba(OH)a]-r r rw rm.s u 1 if u... 

When necessary, it may be determined thus 250 c.c. of the juice, neutralised exactly with soda solution, are evaporated on a water-bath to 50-60 c.c. and then introduced quantitatively into a 100 c.c. flask, cleared with a little lead acetate, made up to the mark, allowed to settle and filtered. To 80 c.c. of the filtrate, placed in another 100 c.c. flask, is added drop by drop sodium sulphate or phosphate solution until the excess of lead is completely precipitated it is then made up to the mark and filtered, and 50 c.c. of the filtrate (corresponding with 100 c.c. of juice) used for the determination of the invert sugar. This may be effected by Herzfeld s method, to be described later (see Raw Sugar). 

Detection of Sulphur Dioxide.—This test is made on sugars from juices decolorised by means of sulphurous acid. To a solution of 10-15 grams of the sugar in about 25 c.c. of water in a flask are added a scrap of pure zinc (or 0-3-0-4 gram of magnesium wire) and 5 c.c. of pure hydrochloric acid. In presence of sulphur dioxide, hydrogen sulphide is evolved and may be detected by the odour or by means of a strip of lead acetate paper. 

With dry slices, the half-normal weight is introduced with basic lead acetate into a 200 c.c. flask and the volume made up to 206 c.c. or 12 64 grams of substance are made up to 200 Mohr c.c. or 12 62 grams up to 200 true c.c. The polarisation in a 20 cm. tube, multiplied by 4, gives the percentage of sugar. 

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