The amount of oxygen used by the suitable microorganisms present in water during five days at 20^(@)C is called as BOD. For pure water BOD is about 1 ppm fairly pure water 3 ppm and doubtful purity 5 ppm the municipal sewage has BOD values 100-4000 ppm. BOD= Number of moles of O_2 required / Number of liters of water sample The BOD values of three water sample x,y and z are 5 mg/litre, 16 mg/Litre and 400 mg/Litre respectively the more polluted sample of water is

The amount of oxygen used by the suitable microorganisms present in wa

1.	The amount of oxygen used by the suitable microorganisms present in water during five days at 20^(@)C is called as BOD. For pure water BOD is about 1 ppm fairly pure water 3 ppm and doubtful purity 5 ppm the municipal sewage has BOD values 100-4000 ppm. BOD= Number of moles of O_2 required / Number of liters of water sample The BOD values of three water sample x,y and z are 5 mg/litre, 16 mg/Litre and 400 mg/Litre respectively the more polluted sample of water is
Answer» x y z all are EQUALLY polluted Answer :C