Essentials of chemistry : inorganic and organic, for the use of students in medicine / by R.A. Witthaus.

  • Rudolph August Witthaus
Date:
1879, ©1878
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Licence: Public Domain Mark

Credit: Essentials of chemistry : inorganic and organic, for the use of students in medicine / by R.A. Witthaus. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    To detect acids not already found, proceed as follows : 1. Boil concentrated N03H with a portion of the solid: a. No colored vapors are given off; dilute N03H so*.., filter, add sol. N03Ag ; a white ppt Chloride. b. Violet vapors are given off, which give a blue color with water containing starch paste Iodide. c. Brown vapors are given off; dilute N03H sol. with muc*h H20, add sol. BaCl2 ; a white ppt.. .Sulphide. d. No reaction as in a. &, and c 2 2. Dissolve solid in HC1, dilute, filter, add sol. BaCl2: a. White ppt Sulphate, [If the base have been found by I. 1 to 11, and the acid have not been found as above, oxalic and phosphoric acids are yet to be searched for; this is done with the fluid from which the base has been separated according to I. 6, acids.] III. The substance is a salt insoluble in water and in acids. 1. Moisten the solid with (NH4)HS : a. It turns black 2 b. It remains white 3 2. Digest the solid at a gentle heat with (NH4)HS, separate the solution from the residue. Residue. Wash, dissolve in N03H, dilute with H20, and divide into two parts, to 1. Add S04H2 ; a white ppt Lead. 2. Add HC1; a white ppt Silver. Solution. Divide into two parts : 1. Add excess HC1, boil, dilute with H20, add BaCl2 Sulphate, 2. Add N03H, boil, and search for chlorides, bro- mides, and iodides, according to 1.10, acids. 8. Mix solid in fine powder with four times its weight of C03NaK, and fuse ; cool; add H20. boil: a. It dissolves entirely ; add excess HC1 to sol., evap- orate to dryness, there remains a residue, insolu- ble in dil. HC1 Silicic acid. b. A white residue remains, pour off H20, and set aside; wash residue, dissolve in dil. HC1, and test for Ba, Ca, and Sr, according to 1.18. The water which has been set aside is to be tested for SO4H3 and F, for the first by BaC)2 in acid solution, and the second by the action of FH on glass, II. 1.