Quantitative chemical analysis / by C. Remigius Fresenius.

Date:
1870
Catalogue details

Licence: Public Domain Mark

Credit: Quantitative chemical analysis / by C. Remigius Fresenius. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    EXERCISES, COMPRISING THE MOST COMMON METHODS OF QUANTITATIVE ANALYSIS. Determination. Before beginning work, read over tbe directions given under Weighing (p. 17) Filtration and Washing of T'recipitates, Drying of Precipitates, and Ignition of Precipitates (pp. 10-12). Put the weights and results in a book: the mode of entering these in the book is given once for all under the first exercise. The book should be taken to the balance, so that the weights may be entered at the moment of weighing. The results should always be compared with the theoretical re- sults obtained by calculation. Tou should not leave any exercise until you have obtained two results sufficiently near to the theory. No limit of error can be assigned which shall be universally appli- cable. Determination of Lead. As sulphate. By ignition. Weigh a porcelain crucible, put into it about '5 grm. of nitrate of lead and weigh again, moisten it with strong sulphuric acid, proceed as directed p. 73, allow to cool, and weigh. Enter the weights and results as follows :— I. Crucible + Pb (NOJ, . . 12-619 ' Crucible 12-102 Pb (NO^)^ taken .... -517 Crucible + Pb SO, . . . 12-572 Crucible 12102 Pb SO, found 470 Pb in Pb (N0„), taken . . -32.3 Pb in Pb SO, found . . . -321 II. 13 4] 6 12-947 •469 13.378 12-947 •431 •293 •294 Error •002 — •001 +