Anions in non saline waters - Determination of Anions in Natural and Treated Waters - page 235

Added Found Recovered

River water none 5.0
5.0 10.3 5.3 106
10.0 15.2 10.2 102
River water none 1.4
5.0 6.4 5.0 100
10.0 10.8 9.4 94
Lake water none 2.2
5.0 7.2 5.0 100
10.0 12.5 10.3 103
Pond water none 3.0
5.0 8.1 5.1 102
10.0 12.8 9.8 98
Well water none 2.4
5.0 7.6 5.2 104
10.0 12.7 10.3 103
Rain water none 2.6
5.0 7.8 5.2 104
10.0 13.2 10.6 106
Irrigation water none 4.9
5.0 10.0 5.1 102
10.0 14.3 9.4 94
Irrigation water none 5.3
5.0 10.3 5.0 100
10.0 14.9 9.6 96
a Evaluation of recoveries of nitrite was based on the addition of nitrite to 16ml of sample solution
in a 20ml calibrated flask
Source: Reproduced with permission from Elsevier Science [525]

seawater. The nitrite is first derivatised by diazotisation with sulphanilamide and then
coupled with 1-naphthylamine to form an azo dye. This azo dye adsorbs on the mercury
drop electrode and its reduction is fully reversible. The concentration of the dye is
linearly related to the height of the reduction peak for concentrations of nitrite in the
range 0.3-200nM. The relative standard deviation was 2% for a concentration of 4nM
nitrite, and the detection limit as 0.3nM for an adsorption time of 60s.