MIL-DTL-382E
b. Add 20 milliliters of buffer solution and 6-10 drops of Eriochrome Black T indicator.
Titrate with EDTA to a color change of red to blue against a reflected light background.
There should be no red color remaining. VA = Volume of EDTA used in milliliters.
X = Milligrams of magnesium per milliliter EDTA =
Where:
WA = Actual weight of magnesium used in grams.
VA = Volume of EDTA used in milliliters.
4.5.3.1.1.3 Procedure.
a. Weigh approximately 1 gram (± 0.2 mg) of sample into a 250 milliliter beaker. WB =
weight of actual sample used.
b. Add 50 milliliters of 0.1 N chromic acid to the sample and allow to stand for 15 minutes,
swirling the beaker every five minutes. Transfer the sample to a 30 milliliter, fine
porosity sintered glass crucible and wash the sample with 25 milliliter portions of
distilled water 6 times. The last washing should be colorless.
c. Wash the sample back into the original beaker with distilled water.
d. Treat the crucible with two 10 milliliter portions of 10 % hydrochloric acid to dissolve
any metal remaining in it, returning the washings into the beaker with distilled water.
Cover the beaker with a watch glass.
e. Add 10 milliliters of concentrated hydrochloric acid in small amounts to the sample.
Gradually heat the beaker to 100oC maximum to dissolve any remaining metal.
f. Cool and transfer the solution to a 500 milliliter volumetric flask.
g. Dilute the solution to the 500 milliliter mark with distilled water and mix.
h. Pipette 50.00 milliliters of this solution into a 600 milliliter beaker.
i. Dilute the sample solution to 300 milliliters with distilled water.
j. Add 20 milliliters of buffer solution and 6-10 drops of Eriochrome Black T indicator to
the sample solution. Titrate with EDTA to a color change of red to blue against a
reflected light background. There should be no red color remaining. VB = Volume of
EDTA used in milliliters.
% metallic magnesium =
Where:
X = Milligrams of magnesium per milliliter EDTA.
VB = Volume of EDTA used in milliliters.
WB = weight of actual sample used.
11
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business