Small, colourless crystals or white powder. Very slightly soluble in water and in glycerine: freely soluble in acetone, in alcohol, in ether and in propylene glycol.
B.Infrared Absorption <197M>
Between 68°C and 72°C
Organic volatile impurities
Method IV <467>: meets the requirements.
Heat 0.75 g in 15 mL of water at80o for 1 minute, cool, and filter: the filtrate is neutral or acid to litmus. To 10 mL of the filtrate add 0.20 mLof 0.1 N sodium hydroxide and 2 drop of methyl red TS : the solution is yellow.
Loss on drying
Dry it over silica gel for 5 hours: it loses not more than 0.5 % of its weight.