LaMotte SMART 3 Electronic Soil Lab - Manual (Page 71)

SMART3 Soil 1.11 71
NITRATE-NITROGEN – LOW RANGE
CADMIUM REDUCTION METHOD • CODE 3649-SC
QUANTITY CONTENTS CODE
2 x 60 mL *Mixed Acid Reagent *V-6278-H
5 g *Nitrate Reducing Reagent *V-6279-C
1 Spoon, 0.1 g, plastic 0699
1 Dispenser Cap 0692
*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.
Nitrogen is a component of the chlorophyll (green color) in plants, thus
giving plants the rich green color characteristic of a healthy plant. Nitrogen
promotes succulence in forage crops and leafy vegetables. When used at
the recommended rates, nitrogen improves the quality of leaf crops. It also
simulates the utilization of phosphorus, potassium and other essential nutrient
elements. The above-ground growth of plants is enhanced with nitrogen.
Nitrogen hastens crop maturity (assuming all other nutrients are adequately
supplied and excessive nitrogen rates are not applied). Nitrogen is very
influential in fruit sizing.
APPLICATION: 0.00-300.00 lb/acre Nitrate-Nitrogen
METHOD: Powdered cadmium is used to reduce nitrate to nitrite.
The nitrite that is originally present plus reduced
nitrate is determined by diazotizing sulfanilamide
and coupling with N-(1 naphthyl)-ethylenediamine
dihydrochloride to form a highly colored azo dye which
is measured colorimetrically.
INTERFERENCES: Strong oxiding and reducing substances interfere. Low
results might be obtained for samples that contain high
concentrations of iron and copper.
Test P
rocedures