The Orthotolidine Reagent for Free Chlorine in Water
The Orthotolidine Reagent for Free Chlorine in Water. ORTHOTOLIDINE is most coomon test Reagent to detect Chlorine during Water distillation, Salts, Hypochlorite, Alkalinity process.
Orthotolidine used as a qualitative test for detection of minute amounts of free chlorine and hypochlorites.
With small amounts of free chlorine, a deep yellow color is produced with the orthotolidine reagent.
During tratment with hypochlorite, a green color appeared which gradually deepened and changed to yellow and finally to deep red as the concentration of free chlorine increased.