Hach DR/700 - Page 418

52-92
MANGANESE, HR, continued
4. Fill a 10-mL cell
to the 10 mL line with
sample.
Note: A 25-mL sample
can be tested by using
25-mL sample cells and
optional reagents.
5. Add the contents
of one Buffer Powder
Pillow, citrate type.
Swirl to mix.
Note: For proof of
accuracy, use a 5.0 mg/L
manganese standard
solution (preparation
given in Accuracy
Check) in place of the
sample.
6. Add the contents
of one Sodium
Periodate Powder
Pillow to the sample
cell (the prepared
sample). Cap and
invert several times to
mix.
Note: A violet color will
develop if manganese is
present.
Note: Accuracy is not
affected by undissolved
powder.
7. Wait 2 minutes. 8. Fill a 10-mL cell
to the 10-mL line
with sample (the
blank). Cap.
9. Place the blank in
the cell holder.
Note: In bright sunlight
it may be necessary to
close the cell
compartment cover.
2 minutes