Copy 1

Outlines of the course of qualitative analysis followed in the Giessen laboratory / By Henry Will ; With a preface by Baron Liebig.

  • Heinrich Will
Date:
1846
Catalogue details

Licence: Public Domain Mark

Credit: Outlines of the course of qualitative analysis followed in the Giessen laboratory / By Henry Will ; With a preface by Baron Liebig. Source: Wellcome Collection.

    38/152 page 22
    f. OXIDE OF ZINC. Zn O. Most salts of this oxide are soluble in water, and all of them in hydrochloric acid. From salts containing weak acids, such as acetic acid, or from salts with mineral acids m the presence of an alkaline acetate, oxide of zinc is completely thrown down by hydrosulphuric acid in the form of white sulphide of zinc, ZnS, which is insoluble in potassa; but if the solution contains a sufficient quantity of free minéral acid, hydrosulphuric acid produces no precipitate. Sulphide of ammonium precipitates the zinc-salts completely as sulphides. Caustic alkalies throw down this oxide in the form of a white hydrate, HO, ZnO, which is easily soluble in an excess of the precipitant. The carbonates of the fixed alkalies produce a basic carbonate of zinc, 3 (HO, ZnO), 2 (ZnO, CO.), insoluble im the precipi- tant, but soluble in chloride of ammonium, the presence of which, therefore, prevents its formation. Carbonate of ammonia precipitates carbonate of zinc, which is readily dissolved in an excess of the precipitant. The carbonates of the alkaline earths produce no precipitate with zinc-salts. The compounds of zine, when exposed with carbonate of soda upon charcoal to the imner flame of the blowpipe, produce a white incrustation of oxide of zimc. When moistened with a solution of cobalt and strongly heated, they assume a green colour. [g- SESQUIOXIDE OF URANIUM. ] UE, (Os: The salts of this sesquioxide are soluble in water or hydrochloric acid, forming a yellow-coloured solution. Hydrosulphuric acid reduces them to salts of the oxide which are easily reconverted into salts of sesquioxide by exposure to the atmosphere, or by the action of nitric acid even in the cold.
    digitised image 1
    digitised image 2
    digitised image 3