134 PRACTICAL ORGANIC CHEMISTRY of cold water in a clean beaker. Add a drop of phenolphthalein solu-tion. A deep pink coloration is produced, owing to the free sodium hydroxide formed in the above hydrolysis. Now by means of a small pipette or a fine glass tube, add very dilute sulphuric acid dr o p by drop until the pink coloration is just discharged. In a few seconds the pink coloration becomes again perceptible, and rapidly deepens in tint. The sulphuric acid may again be added, and the process repeated several times. The addition of the sulphuric acid first neutralises the sodium hydrox-ide, and then gives a weakly acidic and therefore colourless solution. The sodium derivative (A) then undergoes further partial hydrolysis in order to re-establish the original equilibrium, and the sodium hydroxide thus formed again produces the pink coloration, which increases in depth as the hydrolysis proceeds. When the above tests have been completed, wash thoroughly with
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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.