Question:
For wastewater coming from a wood pulping industry, Chemical Oxygen Demand (COD) and 5-day Biochemical Oxygen Demand (BOD\(_5\)) were determined. For this wastewater, which of the following statement(s) is/are correct?
For wastewater coming from a wood pulping industry, Chemical Oxygen Demand (COD) and 5-day Biochemical Oxygen Demand (BOD\(_5\)) were determined. For this wastewater, which of the following statement(s) is/are correct?
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COD is always greater than or equal to BOD, as BOD measures only the biodegradable part of the total oxygen demand.
Updated On: Jan 11, 2026
- COD \(>\) BOD\(_5\)
- COD \( \neq \) BOD\(_5\)
- COD < BOD\(_5\)
- COD = BOD\(_5\)
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The Correct Option is A, B
Solution and Explanation
For wastewater from the wood pulping industry, the Chemical Oxygen Demand (COD) is typically higher than the Biochemical Oxygen Demand (BOD\(_5\)) because the COD measures the total oxygen required to oxidize all organic and inorganic substances, while the BOD\(_5\) measures the oxygen demand due to biodegradable organic matter only. Therefore, COD is generally greater than BOD\(_5\). Additionally, the values of COD and BOD\(_5\) are not equal because COD also includes oxygen demand from non-biodegradable substances.
Thus, the correct answers are:
\[
\text{(A) COD \(>\) BOD\(_5\)}, \text{(B) COD} \neq \text{BOD\(_5\)}.
\]
Final Answer:
(A) COD > BOD\(_5\), (B) COD \( \neq \) BOD\(_5\).
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