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JEE Main20231 Feb 2023Evening ShiftChemistryRedox ReactionsActual

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 for volumetric analysis, its concentration should be checked before the use. Reason (R) : On aging, KOH solution absorbs atmospheric CO 2 . In the light of the above statements, choose the correct answer from the options given below.

Options

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

Correct answer

C. Both (A) and (R) are correct and (R) is the correct explanation of (A)

Step-by-step solution

KOH absorb CO 2 based on the following reaction: CO 2 ( g )   +   2 KOH ( aq )   →   K 2 CO 3 ( aq )   +   H 2 O ( l ) Thus, concentration of Carbon dioxide decreases over time, prior to volumetric analysis concentration of potassium hydroxide should be checked.

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