Introduce 0.250 g to 1.000 g of the substance to be examined, according to the vinyl acetate content of the copolymer to be examined, into a 300 ml conical flask with a ground-glass neck containing a magnetic stirrer. Add 40 ml of xylene R. Boil under a reflux condenser with stirring for 4 h. Stirring continuously, allow to cool until precipitation begins before slowly adding 25.0 ml of alcoholic potassium hydroxide solution R1. Boil again under a reflux condenser with stirring for 3 h. Allow to cool with continued stirring, rinse the condenser with 50 ml of water R and add 30.0 ml of 0.05 M sulphuric acid to the flask. Transfer the contents of the flask into a 400 ml beaker; rinse the flask with two quantities, each of 50 ml, of a 200 g/l solution of anhydrous sodium sulphate R and three quantities, each of 20 ml, of water R and add all the rinsings to the beaker containing the initial solution. Titrate the excess sulphuric acid with 0.1 M sodium hydroxide, determining the end-point potentiometrically (2.2.20). Carry out a blank titration.

1 ml of 0.05Msulphuric acid is equivalent to 8.609 mg of vinyl acetate.

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Supplements For Diabetics

All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.

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