Identification
A:
Dissolve about 200 mg of Menadiol Sodium Diphosphate in 10 mL of water, add 10 mL of 2 N sulfuric acid, 10 mL of 0.1 N ceric sulfate, and 1 mL of 30 percent hydrogen peroxide previously diluted with 5 mL of water, and extract the solution with two 10-mL portions of chloroform. Gently evaporate the clear chloroform solution on a steam bath to dryness, and dry the residue at 80
for 1 hour: the menadione so obtained melts between 104
and 107
.
B:
To 50 mg of the dried residue obtained in
Identification test
A add 5 mL of water, then add 75 mg of sodium bisulfite, and heat on a steam bath, shaking vigorously until the substance is dissolved and the solution is practically colorless. Dilute with water to 50 mL, and mix. To 2 mL of the solution add 2 mL of alcoholic ammonia (prepared by mixing equal volumes of alcohol and ammonium hydroxide), shake, and add 3 drops of ethyl cyanoacetate: a deep purplish blue color is produced, and on the addition of 1 mL of sodium hydroxide solution (1 in 3), it changes to green and then to yellow.
C:
To about 20 mg contained in a small beaker add 1 mL of water, 2 drops of nitric acid, and 1 mL of sulfuric acid, and heat slowly to the evolution of white fumes. Cool, cautiously dilute with water to about 10 mL, and filter if not clear. Render the filtrate slightly alkaline to litmus with 6 N ammonium hydroxide, then render it acid with nitric acid, and add to the warm solution 3 mL of
ammonium molybdate TS: a yellow precipitate is formed within a few minutes.