Hach DR/700 Procedures Manual page 226

SULFATE,
continued
4.
Prepare the
displayed standard.
For each mg/L
displayed, pipet 1.00
mL of 1000 mg/L of
Sulfate Standard
Solution into a
1000-mL volumetric
flask. Add
demineralized water
to the mark. Cap and
invert 10 times to
mix.
Note: For example: to
make a 50 mg/L
standard, pipet 50.0 mL
into the flask, For a
zero concentration
standard, use only
demineralized water.
5.
Fill a 10-mL cell
to the 10-mL line
with the displayed
sample. Cap.
45-54
6.
Fill a 10-mL cell
to the 10-mL line
with sample.
Note: Filter highly
colored or turbid
samples. Use labware
listed under Optional
Apparatus to filter.
Note: A 25-mL sample
can be tested by using
25-mL sample cells and
optional reagents.