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Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : An aqueous solution of KOH when used for volumetric analysis, its concentration should be checked before the use. Reason (R) : On aging, KOH solution absorbs atmospheric CO2. In the light of the above statements, choose the correct answer from the options given below :

1. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
2. Both (A) and (R) are correct and (R) is the correct explanation of (A)
3. (A) is correct but (R) is not correct
4. (A) is not correct but (R) is correct

Correct answer: Both (A) and (R) are correct and (R) is the correct explanation of (A)

Solution

The assertion is correct because the concentration of KOH must be verified before use in volumetric analysis to ensure accurate results. The reason is also correct, as KOH solution can absorb CO2 from the atmosphere, leading to changes in concentration, which directly supports the need for checking its concentration.

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