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. 1895 Excerpt: ...oxidation. When most of the precipitate is on the filter, wash the tube inside and out, and place it clean end downwards in a filter-drier. Thoroughly rinse out the beaker, washing any easily removed precipitate on to the filter; but it is not necessary to detach any strongly adhering film; the precipitate and paper ...
Read More
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. 1895 Excerpt: ...oxidation. When most of the precipitate is on the filter, wash the tube inside and out, and place it clean end downwards in a filter-drier. Thoroughly rinse out the beaker, washing any easily removed precipitate on to the filter; but it is not necessary to detach any strongly adhering film; the precipitate and paper are washed with hot water, and are then allowed to drain. Re-dissolving the preeipitate.--Carefully detach the paper from the funnel, and place it bodily in the beaker in which the precipitation took place; put on the cover, and add about 35 cc. of strong nitric acid, spec, gravity 143. Boil the mass till the filter-paper is decomposed with evolution of deep red-brown fumes, and only suspended fibres remain in the acid. Next cautiously add, about a gramme at a time, well boiling between each addition, pure crystallized chlorate of potash, till the solution becomes elear from fibres, and only a globule or two of yellow sulphur remain. The chlorate of potash is best added by drawing the cover of the beaker a little aside, and quickly dropping it into the liquid from a slip of stiff paper; several grammes will be required to completely free the solution from organic matter. Then heat the black end of the precipitation tube in the beaker till free from adhering film, rinse it inside and out, and remove. Evaporation to low bulk.--The acid solution is now evaporated, at first keeping the cover on the beaker, to a volume of not more than 5 cc, when potassium salts will have crystallized out in some quantity. These are completely taken up by boiling, after diluting with 50 cc. of water. Neutralizing.--The solution is next treated with pure sodic hydrate till a faint permanent precipitate is obtained, which is re-dissolved in a few drops of hydrochloric ...
Read Less
