A:
To 3 mL of water contained in a small flask add about 0.1 mL of it and 0.5 mL of 1 N hydrochloric acid, and agitate the mixture until clear. Add 20 mL of trinitrophenol TS, insert the stopper in the flask, shake vigorously for a few minutes, and allow to stand for 2 hours. Filter, wash the precipitate with about 20 mL of cold water, and dry in vacuum at 60
for 4 hours: the picrate so obtained melts between 108
and 110
(see
Melting Range or Temperature 
741
).
[Caution: Picrates may explode.
]
B:
A solution, prepared as directed in
Identification test
A, yields a brown precipitate with
iodine TS and a white precipitate with mercuric-potassium iodide TS.
;)
-dimethyl-, (±)-.