LaMotte SMART Spectro Spectrophotometer - Manual (Page 154)

DISSOLVED OXYGEN
WINKLER COLORIMETRIC METHOD • CODE 3688-SC
QUANTITY CONTENTS CODE
30 mL *Manganese Sulfate Solution *4167-G
30 mL *Alkaline Potassium Iodide Azide *7166-G
30 mL *Sulfuric Acid 1:1 *6141WT-G
1 Sample Tube, screw cap 29180
1 Cap 28570
*WARNING: Reagents marked with an * are considered to be potential health
hazards. To view or print a Material Safety Data Sheet (MSDS) for these reagents
go to www.lamotte.com. To obtain a printed copy, contact LaMotte by e-mail,
phone or fax.
Dissolved oxygen is vital to the survival of aquatic organisms. Naturally present,
dissolved oxygen enters the water when plants photosynthesize. Wind and wave
action also cause oxygen from the air to dissolve into water. Dissolved oxygen is
consumed by aquatic animals and by the oxidation, or chemical breakdown, of
dead and decaying plants and animals. The concentration of dissolved oxygen
in natural waters can range from 0 to 14 ppm and is effected by temperature and
salinity.
APPLICATION: Drinking and surface waters; domestic and industrial
wastewaters.
RANGE: 0.00–12.00 ppm Dissolved Oxygen
MDL: 0.25 ppm
METHOD: This method uses the azide modifi cation of the Winkler
Method with a colorimetric determination of the yellow
iodine produced from the reaction with the dissolved
oxygen.
INTERFERENCES: The presence of other oxidizing agents may cause positive
interferences. Reducing may cause negative interferences.
Nitrite interferences are eliminated with the azide
modifi cation.
SMART Spectro Test Procedures 2.11 DISSOLVED OXYGEN
Test P
rocedures