3.1. Effect of sulfuric acid concentration
The redox reaction of iodide and nitrite takes place in the acidic
solution, thus the influence of acidity on the reaction of nitrite with
iodide was studied. The cloud point extraction was performed in
different concentrations of sulfuric acid. The results presented in
Fig. 1indicate that the highest absorbance is obtained after cloud
point extraction of triiodide when redox reaction occurs at an acid
concentration of 0.012 mol L
−1
. Therefore this concentration was
selected as optimum and 3 mL of 0.1 mol L
−1
sulfuric acid was added
to the 25 mL solution in order to maintain this concentration