COD stands for which term?

COD stands for which term?

• A. Chemical Oxygen Depletion
• B. Chemical Oxygen Demand
• C. Chemical Oxidation Demand
• D. Chemical Oxygen Deficit

Answer: (B)

In wastewater analysis, COD represents the amount of oxygen required to chemically oxidize the organic matter in a water sample. The term stands for Chemical Oxygen Demand. A strong chemical oxidant, typically potassium dichromate in acidic solution, oxidizes organics quickly, usually within about two hours, and the oxygen that would be consumed is reported as milligrams per liter of oxygen. This measurement reflects the overall pollutant load, including both biodegradable and non-biodegradable organics, making COD a fast proxy for how much oxygen would be needed if the water were discharged and treated downstream. It’s different from biological oxygen demand, which measures oxygen use by microorganisms over a long period, and the other options are not standard terms used in this context.

In wastewater analysis, COD represents the amount of oxygen required to chemically oxidize the organic matter in a water sample. The term stands for Chemical Oxygen Demand. A strong chemical oxidant, typically potassium dichromate in acidic solution, oxidizes organics quickly, usually within about two hours, and the oxygen that would be consumed is reported as milligrams per liter of oxygen. This measurement reflects the overall pollutant load, including both biodegradable and non-biodegradable organics, making COD a fast proxy for how much oxygen would be needed if the water were discharged and treated downstream. It’s different from biological oxygen demand, which measures oxygen use by microorganisms over a long period, and the other options are not standard terms used in this context.