What is Biochemical Oxygen Demand (BOD) ?

What is Chemical Oxygen Demand (COD) ?

Biochemical Oxygen Demand (BOD) in river water

Biochemical Oxygen Demand (BOD) in a river water

Biochemical Oxygen Demand (BOD) may not be a good index for pollution for water bodies receiving effluents from

Among the following, find.the number of correct statements? Sea water and trees are big sinks for carbondioxide. Geater the chemical oxygen demand (COD) and biochemical oxygen demand (BOD) values, greater is the extent of pollution. Lesser the threshold limit value (TLV), greater the toxicity Ozone layer present in stratosphere acts as protective umbrella form hamful sunrays. Flouride ion in drinking water is detected by using zirconium alizarin - S dye. The dye loses its colour in the presence of flouride. Human ear can tolerate the sound upto the intensity 60 decibles.

In which one of the following the BOD (Bio-chemical Oxygen Demand) of sewage (S), distillery effluent (DE), paper mill effluent (PE) and sugar mill effluent (SE) have been arranged in ascending order ?

High value of BOD (Biochemical Oxygen Demond) shows