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. 1874 edition. Excerpt: ...forms, it is collected on a very small filter, . and tested as directed on p. 120. 2. Wet Reactions. (a) Ammonia produces a white precipitate of aluminic hydrate, Al(H0)3. (b) Ammonium sulphide produces the same precipitate. (c) Caustic soda or potash throws down the same precipitate; it is soluble in ...
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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. 1874 edition. Excerpt: ...forms, it is collected on a very small filter, . and tested as directed on p. 120. 2. Wet Reactions. (a) Ammonia produces a white precipitate of aluminic hydrate, Al(H0)3. (b) Ammonium sulphide produces the same precipitate. (c) Caustic soda or potash throws down the same precipitate; it is soluble in an excess of the reagent, but reprecipitated by ammonium chloride. (d) Barium carbonate also precipitates aluminic hydrate mixed with basic salt. III. Chromium.--Potassium bichromate is used for the tests. 1. Dry Reactions.--Heated on platinum foil with potassium nitrate, a yellow mass of potassium chromate (K2Cr04), soluble in water, is formed. On borax bead in oxidising and reducing flames, gives a green coloured bead. 2. Wet Reactions.--Dissolve a few crystals of potassium bichromate in water, add a little hydrochloric acid and alcohol, and boil until the liquid is dark green in colour. This solution now contains chromium chloride: K2Cr207 + 8HCI + 3C2H60 = Cr2Cl6 + 2KCI + 3C2H40 + 7H20 (a) Ammonia precipitates greyish-green chromic hydrate, Cr(0H)3. (b) Caustic soda or potash produces the same precipitate. It is soluble in an excess of the precipitant, but is reprecipitated on boiling for a few minutes. Chromium in certain compounds (the chromates) plays a chlorous rather than a basylous part. Its presence in such substances may be detected as follows. Using as example a solution of potassium dichromate in water. (a) Ammonium sulphide throws down a brown precipitate consisting chiefly of chromium chromate, Cra(Cr04)3, the solution now containing potassium chromate, thus--S(KaCra07) + 3(NH4)aS = Cra(Cr04)3 + S3 + 5KaCr04 + 6NH3 + 3H.O. If ammonium sulphide be added in excess and the liquid boiled, green chromic hydrate, Cr(0H)3, mixed with..
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Add this copy of Qualitative Chemical Analysis and Laboratory Practice, to cart. $59.74, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Hialeah, FL, UNITED STATES, published 2016 by Palala Press.
