QUANTITATIVE ANALYSIS 505 that almost all the suspended silver halide is drawn over in one opera-tion. Then add 3 ml. of distilled water, shake the mixture, and draw it over by suction a little at a time. Repeat this operation twice more, first rubbing down gently with the end of the tube K any particles of silver chloride adhering to the walls of the Carius tube. Finally add two separate portions of ethanol, each of 5 ml., and draw them over. Remove the tube K and the bung L. Examine the underside of the bung for any particles of silver halide that might be adhering: wash any such particles down into the funnel G with a small quantity of ethanol. Then wash the inside wails of the funnel, under gentle suction, with 5 ml. of ethanol from a wash-bottle, and finally the walls and precipitate with two 5 ml. portions of acetone, and drain well. Drying and weighing the silver halide. Remove the funnel G from the bung J, wipe it with a clean cloth, and close the wide end by gently inserting a
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