This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1902 edition. Excerpt: ...no black stain or deposit appears on the dish the gas may be considered pure for the present purpose. Now prepare a very dilute solution of sodium arsenite, or arsenous acid, and pour 5 drops of this through I he funnel tube into the generator. Hold the porcelain dish again in the flame and observe ...
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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1902 edition. Excerpt: ...no black stain or deposit appears on the dish the gas may be considered pure for the present purpose. Now prepare a very dilute solution of sodium arsenite, or arsenous acid, and pour 5 drops of this through I he funnel tube into the generator. Hold the porcelain dish again in the flame and observe that after a time a shining black deposit of arsenic collects. Allow several of these stains or deposits to form on different parts of the dish. (The stains may be further examined as will be explained shorlly.) Next heat the delivery tube with the Bunsen flame a short distance in front of the central narrowed part, that is between the generator and the constriction. At a high temperature the hydrogen arsenide decomposes, yielding arsenic, which precipitates on the cooler part of the tiibe, and hydrogen, which burns at the end. If the heat is applied at the right point the arsenic deposit forms in the contracted portion of the tube where it can be readily seen. The liberated arsenic, being slightly volatile, is deposited some distance beyond the point most strongly heated. The stains in the dish may now be tested. Pour in a few drops of a fresh solution of sodium hypochlorite and allow this to flow around the dish. The deposit goes into solution almost instantly. This behavior distinguishes arsenic from very similar antimony stains to be described later. In performing this experiment care must be taken to have the corks and fittings of the apparatus perfectly tight, and to keep the gas burning, after the addition of the arsenic solution. The experiment just described constitutes what is called the Marsh test for arsenic. It is exceedingly delicate, and further details concerning it may be found in books on qualitative analysis, as it is...
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Add this copy of Elements of General Chemistry With Experiments to cart. $22.29, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of Elements of General Chemistry With Experiments to cart. $33.45, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of Elements of General Chemistry With Experiments to cart. $35.34, new condition, Sold by Ria Christie Books rated 5.0 out of 5 stars, ships from Uxbridge, MIDDLESEX, UNITED KINGDOM, published 2022 by Legare Street Press.
Add this copy of Elements of General Chemistry With Experiments to cart. $46.22, new condition, Sold by Ria Christie Books rated 5.0 out of 5 stars, ships from Uxbridge, MIDDLESEX, UNITED KINGDOM, published 2022 by Legare Street Press.
Add this copy of Elements of General Chemistry With Experiments to cart. $56.22, new condition, Sold by Booksplease rated 4.0 out of 5 stars, ships from Southport, MERSEYSIDE, UNITED KINGDOM, published 2022 by Legare Street Press.
