Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: 9. Quantitative Estimation.—This is effected volumetrically by means of a normal solution of potassium hydroxide, phenolphthalein being used as indicator. ACETONE. CH8.CO.CH3 = 57-86. 1. Acetone should boil at 56 to 57 C. and have a specific gravity of 0-812 at o C. 2. When evaporated on the water-bath it should not leave any residue (absence of nonvolatile substances.) 3. Its reaction should be neutral; on evaporating the liquid, neutralised with sodium hydroxide if acid, taking up the dry residue with a little water, and adding a trace of ferric chloride, no bl00d-red coloration should appear (absence of acetic acid). 4. When diluted with water it should yield a clear solution (absence of tarry products), which should not become turbid when treated with silver nitrate, in the cold, or on heating (absence of aldehydes and reducing substances). 5. When shaken with dry calcium chloride it should not give a moist mixture (absence of moisture). 6. Quantitative Estimation.—This is based on the transformation of the acetone into iodoform by means of iodine and potassium hydroxide, and gravimetric determination of the iodoform produced (Kraemer). ALCOHOL (ETHYL ALCOHOL). CaH8OH = 46-05. 1. Alcohol should be colourless and volatilise completely when heated on platinum foil (absence of non-volatile mineral matter), and should remain colourless after the addition of ammonia (absence of tarry substances and tannin derived from the casks). 2. It should have the normal physical properties (boiling point and specific gravity). If these should be higher than normal the presence of foreign substances will be indicated. 3. It should not contain water. This, of course, only refers to absolute alcohol. When completely anhydrous it should not cause copper sulphate ...