Hach DR2400 - Page 513

Nitrogen, Total
Nitrogen, Total
NitrogenTot_UniCell_Other_PSD_Eng_Ody.fm Page 5 of 6
Summary of Method
Bound nitrogen, both inorganically and organically bound, is oxidized to nitrate
by digestion with peroxodisulphate. The nitrate ions react with
2,6-dimethylphenol in a solution of sulphuric and phosphoric acids to form a
nitrophenol. Results are expressed as mg/L N or mg/L TN
b
(Total Bound
Nitrogen) with the same numeric value. Measurements are taken at 370 nm.
REQUIRED REAGENTS AND STANDARDS
Description Unit Cat. No.
Nitrogen, Total, UniCell™ HCT 111................................................................................. 23/pkg...............HCT 111
OPTIONAL REAGENTS
Nitrogen-Nitrate (NO
3
–N) Standard Solution, 1000-mg/L ......................................... 500 mL...............12792-49
Sodium Hydroxide Standard Solution, 5.0 N................................................................. 50 mL SCDB .......2450-26
Sulfuric Acid, ACS.............................................................................................................. 500 mL...................979-49
OPTIONAL EQUIPMENT AND SUPPLIES
Digital Reactor Block.......................................................................................................... each....................DRB 100
Flask, volumetric, 100-mL ................................................................................................. each....................14574-42
Graduated cylinder, mixing, 100-mL............................................................................... each....................20886-42
pH Paper.............................................................................................................................. 100/pkg.............26013-00
Pipettor, (Jencons) 1–5 mL................................................................................................. each....................27951-00
Replacement tips for 27951-00 .......................................................................................... 100/pkg.............27952-00
Pipettor, (Jencons) 100–1000 µL........................................................................................ each....................27949-00
Replacement tips for 27949-00 .......................................................................................... 400/pkg.............27950-00
Reaction Tube ...................................................................................................................... 5/pkg................ HCT 211
Test tube rack, cooling........................................................................................................ each....................18641-00