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|  MIL-S-10521K (AR)
4. 5.2.2.2 Potassium chlorate. The filtrate obtained in
4.5.2.2.1 shall be diluted to 250 ml. in an accurately calibrated
volumetric flask. A 25 ml. aliquot shall be transferred with a
calibrated pipette to a 500 ml. Ehrlenmeyer flask, diluted to
approximately 150 ml. and approximately 50 ml. of 18N sulfuric acid
added. The flask shall be stoppered with a rubber stopper equipped
with a Bunsen valve and the contents heated almost to boiling.
Fifty (50) ml. of a standardized solution of approximately four
percent ferrous ammonium sulfate (Mohr's Salt) shall be added, using
a calibrated pipette, and the solution boiled for two minutes,
cooled, the valve loosened, and the excess of Mohr's Salt titrated
with a standardized 0.1N solution of potassium permanganate.
Currently conduct a blank determination using the same quantities of
the same reagents used for the analysis of the sample. The
percentage of potassium chlorate in the sample shall be *calculated
as follows:
Percent of potassium chlorate = .2043 (V-v) N100
divided by W
where:
V = ml. of standard potassium permanganate required for blank
titration, ml.
v = volumne of potassium permanganate required for sample
titration, ml.
N = normality of potassium permanganate solution.
w = weight of original sample, grams.
4.5.2.2.3 Dextrin. The percentage of dextrin in the sample
shall be calculated by subtracting from 100 the combined percentages
of antimony sulfide and potassium chlorate.
4.5.2.3 Flash composition.
4.5.2.3.1 Magnesium. An accurately weighed portion of
approximately one gram of the sample shall be transferred to a 150
ml. beaker . One hundred (100) ml. of water at 25 3C, 77 +
10F, shall be added to the beaker. The contents of the beaker
shall be stirred with a stirring rod for two or three minutes to
dissolve the potassium perchlorate, and the contents filtered by
means of a tared, 30 ml. medium porosity, fritted-glass crucible.
(It is essential that the filtration be carried out immediately
after the completion of the two to three minute stirring period,
otherwise appreciable reaction will result which will adversely
affect the accuracy of the results obtained). The residue shall be
transferred to the crucible quantitatively and washed with five
5-ml. portions of water, and two 5-ml. portions of acetone. The
crucible and contents shall be aspirated for two minutes, dried for
30 minutes at 100 5C., 212 10F, cooled in a desiccator,
and weighed. As much of the residue remaining in the crucible as
practicable, shall be transferred to a 150 ml. beaker. One hundred
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