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A: Value of COD is greater than BOD. R:...

A: Value of COD is greater than BOD.
R: Used oxygen is demanded by some chemicals for oxidation of inorganic and organic pollutants.

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)

C

If Assertion is true statement but Reason is false, then mark (3)

D

If both Assertion and Reason are false statements, then mark (4).

Text Solution

AI Generated Solution

The correct Answer is:
**Step-by-Step Solution:** 1. **Understanding COD and BOD:** - COD stands for Chemical Oxygen Demand, which measures the total amount of oxygen required to chemically oxidize organic and inorganic substances in water. - BOD stands for Biological Oxygen Demand, which measures the amount of dissolved oxygen that microorganisms will consume while decomposing organic matter in water. 2. **Comparison of COD and BOD:** - COD includes the oxygen required for both biodegradable and non-biodegradable substances, while BOD only accounts for the oxygen consumed by microorganisms for biodegradable materials. - Therefore, COD is generally greater than BOD because it encompasses a broader range of substances that require oxygen for oxidation. 3. **Assertion and Reason Analysis:** - The assertion states that "the value of COD is greater than BOD," which we have established as true. - The reason states that "used oxygen is demanded by some chemicals for oxidation of inorganic and organic pollutants," which is also true because COD measures the total oxygen demand including that from chemical reactions. 4. **Conclusion:** - Since both the assertion and reason are true, and the reason correctly explains the assertion, we conclude that the correct answer is that both the assertion and reason are true, and the reason is a correct explanation of the assertion. **Final Answer:** The correct answer is that both the assertion and reason are true, and the reason is a correct explanation of the assertion. ---
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