Prof. Kai Bester , Thankyou for the reply. Yes, i want theoretical value. I have a query regarding the above equation: Will one of the product be NO2 or NO3?
Aarif Shah, If the COD analysis is the standard one with chromate in acid I think the standard balanced reaction will be: C8H9NO2 + 9O2 +H+ -> 8CO2 + 4H2O + NH4+
The combusting reaction suggested by Kai Bester: C8H9NO2 + 11O2 -> 8CO2 + 2½H2O + NO3- + H+ in my opinion overestimate the COD as typically chromic acid is not able to oxidize N(-III) in the standard analysis https://en.wikipedia.org/wiki/Chemical_oxygen_demand.