REACTIONS AND IDENTIFICATION 327 tube whilst still in a horizontal position in order to redistribute the contents: then continue the heating cautiously.) Finally heat the tube strongly in a vertical position for a short time. While the end of the tube is still red-hot, plunge the tube vertically into about 20 ml. of cold distilled water in an evaporating-basin. Boil the contents of the dish gently, allow to cool slightly and then decant the supernatant liquid through a filter. Retain the residue in the basin for the sulphur test. Divide the clear filtrate into two portions. NITROGEN. To one portion of the filtrate, add 2-3 ml. of io°0 aqueous sodium hydroxide solution, then add about 0-2 g. of ferrous sulphate and proceed as in the Lassaignc nitrogen test (p. 322). Note, however, that the final acidification with dilute suphuric acid must be made \\ith care, owing to the vigorous evolu-tion of carbon dioxide from the carbonate present. HALOGEN
This is the end of the preview. Sign up
access the rest of the document.
This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.