Hach DR2400 - Page 426

Nitrate
© Hach Company, 2003. All rights reserved. Printed in the U.S.A. 3/04 1ed
Page 6 of 6 Nitrate_AVPP_HR_CDR_Eng_Ody.fm
HACH COMPANY
WORLD HEADQUARTERS
Telephone: (970) 669-3050
FAX: (970) 669-2932
FOR TECHNICAL ASSISTANCE, PRICE INFORMATION AND ORDERING:
Call 800-227-4224
Contact the HACH office or distributor serving you.
www.hach.com techhelp@hach.com
In the U.S.A. –
Outside the U.S.A. –
On the Worldwide Web – ; E-mail –
toll-free
Method Performance
Precision
Standard: 10 mg/L NO
3
–
–N
See Section 3.4.3 Precision on page 44 for more information, or if the standard
concentration did not fall within the specified range.
Sensitivity
See Section 3.4.5 Sensitivity on page 44 for more information.
Summary of Method
Cadmium metal reduces nitrates in the sample to nitrite. The nitrite ion reacts in
an acidic medium with sulfanilic acid to form an intermediate diazonium salt.
The salt couples with gentisic acid to form an amber colored solution. Test
results are measured at 500 nm.
Required Reagents
Quantity Required
Description per test Unit Cat. No.
NitraVer
®
5 Nitrate Reagent Powder Pillows (for 10-mL sample)....1 pillow........... 100/pkg.............21061-69
or
NitraVer
®
5 Nitrate Reagent AccuVac
®
Ampul...................................1 ampul........... 25/pkg...............25110-25
Required Apparatus
Sample cell, 10-mL, w/cap......................................................................2 ....................... each....................24276-06
Required Standards
Nitrate Nitrogen Standard Solution, 10.0-mg/L NO
3
–
–N............................................ 500 mL...................307-49
Nitrate Nitrogen Standard Solution, 2-mL PourRite
®
Ampule,
500-mg/L NO
3
–
–N....................................................................................................... 20/pkg...............14260-20
Water, deionized ................................................................................................................. 4 liters ....................272-56
Program 95% Confidence Limits of Distribution
355 8.0–12.0 mg/L NO
3
–
–N
361 9.2–10.8 mg/L NO
3
–
–N
Portion of Curve ∆Abs
∆Concentration
(Program 355)
∆Concentration
(Program 361)
0 ppm 0.010 0.3 mg/L NO
3
–
–N 0.5 mg/L NO
3
–
–N
10 ppm 0.010 0.6 mg/L NO
3
–
–N 0.7 mg/L NO
3
–
–N
30 ppm 0.010 1.0 mg/L NO
3
–
–N 0.8 mg/L NO
3
–
–N