Hach DR/700 Procedures Manual page 464

CHROMIUM, TOTAL,
SUMMARY OF METHOD
Trivalent chromium in the sample is oxidized to the hexavalent form by
hypobromite ion under alkaline conditions. The sample is acidified.
The total chromium content is determined by the 1,5-diphenylcarbohy-
drazide method. Determine trivalent chromium by subtracting the
results of a separate hexavalent chromium test from the results of the
total chromium test.
REQUIRED REAGENTS
Total Chromium Reagent Set (100 Tests) . . . . . . . . . . . . . . . . . . 22425-00
Includes: (2) 2126-66, (2) 12066-66,
(1) 2043-99, (1) 2044-99
Description
Acid Reagent
Powder Pillows. . . . . . . . . . 1 pillow . . . . 50/pkg . . . . . . . . . 2126-66
ChromaVer 3 Chromium
Reagent Powder Pillows . . 1 pillow . . . . 50/pkg . . . . . . . . 12066-66
Chromium 1 Reagent
Powder Pillows . . . . . . . . . 1 pillow . . . . 100/pkg . . . . . . . . 2043-99
Chromium 2 Reagent
Powder Pillows . . . . . . . . . 1 pillow . . . . 100/pkg . . . . . . . . 2044-99
REQUIRED APPARATUS
Bottle, mixing, 25 mL . . . . . . . 1 . . . . . . . . . each . . . . . . . . . . 17042-00
Clippers, for opening
powder pillows . . . . . . . . . 1 . . . . . . . . . each . . . . . . . . . . . 968-00
DR/700 Filter Module
Number 55.01. . . . . . . . . . . 1 . . . . . . . . . each . . . . . . . . . . 46255-00
Water bath and rack . . . . . . . . 1 . . . . . . . . . each . . . . . . . . . . . 1955-99
Select one based on available voltage
1
Hot plate, 3 / " diameter, 120 Vac . . . . . . . . each . . . . . . . . . . 12067-01
2
1
Hot plate, 3 / " diameter, 240 Vac . . . . . . . each . . . . . . . . . . 12067-02
2
OPTIONAL REAGENTS
ChromaVer 3 Reagent Powder Pillows,
for 10 mL samples . . . . . . . . . . . . . . . . . . 100/pkg . . . . . . . 12710-99
continued
Quantity
Per Test Unit
55-16
Cat. No.
Cat. No.