Which of the following statements is CORRECT about BOD?

Explanation

Key Points BOD - It is the amount of dissolved oxygen used by microorganisms to break down organic matter in water. COD - It refers to the Chemical Oxygen Demand i.e. oxygen required to oxidize the biodegradable as well as non-biodegradable organic matter. COD - BOD = Non biodegradable organic matter Important Points Usually less than COD: CORRECT The ratio COD/BOD is defined as the portion of biodegradable organics compared to total (bio + non-bio) degradable organics. This ratio is generally greater than 1 , meaning BOD is less than COD . Biochemical oxygen demand: CORRECT The full form of BOD is Biological or Biochemical Oxygen Demand. A measure of the organic matter present in waste water: CORRECT A low BOD is an indicator of good quality water , while a high BOD indicates polluted water. Therefore, BOD is a measure of the organic matter present in waste water. Hence, all the given options are correct.