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New System of Chemical Philosophy (2 volumes)
New System of Chemical Philosophy - 2 volumes Author:John Dalton Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: with its impurities; which agrees with the results obtained by the other methods. 14. Oxide of zinc. When zinc is exposed to a strong heat it burns with a ... more »brilliant white flame, and a white powder sublimes, which is the oxide of the metal. When dilute sulphuric acid is poured on granulated zinc, hydrogen gas is produced in great abundance and purity; the metal is oxidized at the expence of the water and dissolved in the acid, the oxide may be precipitated by an alkali; it is white both when precipitated and dried, and when heated does not differ from that obtained by combustion. By a violent heat it runs into glass. The quantity of oxygen in zinc oxide is, I think, best estimated by the hydrogen gas produced during the solution; it may also be obtained by direct combustion, or by solution in nitric acid and calcination. Dr. Thomson determines the oxygen by comparison of the weights of real sulphuric acid and metallic zinc in a solution of sulphate of zinc, along with the consideration that the proportion of sulphuric acid and oxygen in the metallic sulphates is known; Mr. Cavendish obtained 356 oz. measures of hydrogen from 1 oz. ofzinc by solution. I dissolved 49 grains of zinc in dilute sulphuric acid and obtained hydrogen, after the rate of 363 grain measures for 1 grain of zinc = 182 measures of oxygen = .24 grain of oxygen. The following are the principal authorities for the quantity of oxygen in zinc oxide, in the order of time. Zinc. Oxygen. 1766. Cavendish 100 + 23.3 1785. Lavoisier 1- 19.6 1790—1800. Wenzel and Proust... f- 25 1801. Desorme and Clement (-21.7 Davy (- 21.95 IJerzelius h 24.4 Gay Lussac + 24.4 Thomson ,. 1- 24.42 My own -)- 24 Now if 24 oxy.: 100 zinc::7 oxy.:29zinc, nearly, which is therefore the weight of an at...« less
ISBN-13: 9780712900027 ISBN-10: 0712900020 Pages:1,117 Edition:Facsimile of 1808 ed Rating: