Division 6.5 Determination

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1. 6.5.1Transfer to the flask a few pieces of porcelain or a few glass beads (5.10.1) and about 10 grams of the anhydrous potassium sulphate (4.2).
2. 6.5.2Transfer into the conical flask (5.7) 50 ml of the boric acid solution (4.5) and four drops of the indicator (4.8). Mix. Place the conical flask under the condenser (5.4) so that the tip of the outlet tube (5.5) is immersed in the boric acid solution. Using a graduated cylinder (5.8), add to the Kjeldahl flask 80 ml of the sodium hydroxide solution (4.6). During this operation, hold the flask in an inclined position so that the sodium hydroxide solution runs down the side of the flask to form a bottom layer.
3. 6.5.3Division 6.5.3