188 PRACTICAL ORGANIC CHEMISTRY C 6 H 5 X 2 HSO 4- HOH- C 6 H 5 OH- X 2- H 2 SO 4 should smell of phenol) and test for phenol by adding bromine water. A brownish-white precipitate of tribromophenol is produced (p. 339). (2) To the cold solution, add about 2 ml. of io% potassium iodide solution. A brisk effervescence of nitrogen occurs, and iodobenzene separates, usually as drops so small that in spite of their density they float on the surface. C 6 H 5 N 2 HSO 4-r KI -> C 6 H 5 I + N, + KHSO 4 (3) (a) Dissolve about 0-5 g. of phenol in a considerable excess of 10% sodium hydroxide solution and cool in ice-water. Pour the diazo-nium solution into this sodium phenoxide solution and note the forma-tion of an orange-yellow solution of the sodium derivative of benzene-azophenol. C 6 H 5 N 2 HSO 4 + HC 6 H 4 ONa -> C 6 H 5 NtNC 6 H 4 ONa -f- H 2 SO 4 The sulphuric acid is of course neutralised at once by the alkaline solution. ( b
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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.