Hach DR/700 Procedures Manual page 178

BARIUM,
continued
4.
Prepare the
displayed standard.
For each 10 mg/L
displayed, pipet
1.00 mL from a
5000-mg/L Barium
Voluette Ampule into
a 500-mL volumetric
flask. Add
demineralized water to
the mark. Cap and
invert 10 times to mix.
Example: To make a
50 mg/L standard, pipet
5.00 mL into the flask.
For a zero standard, use
only demineralized
water.
7.
Quickly invert the
ampul several times
to mix. Wipe off any
liquid or fingerprints.
Note: A white turbidity
will develop if barium is
present.
5.
Collect at least
40 mL of sample in a
50-mL beaker.
Collect at least 40 mL
of the displayed
standard in another
50-mL beaker.
Note: Filter highly
colored or turbid
samples using labware
listed under Optional
Apparatus.
5 minutes
8.
Wait 5 minutes.
Note: The sample
should not be disturbed
during the five minute
turbidity-development
period.
45-6
6.
Fill a Barium
AccuVac Ampul with
the displayed
standard. Fill a
second AccuVac
Ampul with sample.
Note: Keep the tip
immersed while ampul
fills completely.
9.
Insert the
AccuVac Vial
Adapter into the cell
holder.