KOH absorb CO2 based on the following reaction:
CO2(g)+2KOH(aq)→K2CO3(aq)+H2O(l)
Thus, concentration of Carbon dioxide decreases over time, prior to volumetric analysis concentration of potassium hydroxide should be checked.
JEE Main 2023 — Chemistry Physical Chemistry
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 CO2.
In the light of the above statements, choose the correct answer from the options given below.
Held on 1 Feb 2023 · Verified 6 Jul 2026.
(A) is not correct but (R) is correct
Both (A) and (R) are correct but (R) is not the correct explanation of (A)
Both (A) and (R) are correct and (R) is the correct explanation of (A)
(A) is correct but (R) is not correct
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