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Chemistry · PYQ NEET UG 2022
हिन्दीGiven below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): In a particular point defect, an ionic solid is electrically neutral, even if few of its cations are missing from its unit cells. Reason (R): In an ionic solid, Frenkel defect arises due to dislocation of cation from its lattice site to interstitial site, maintaining overall electrical neutrality. In the light of the above statements, choose the most appropriate answer from the options given below:
Correct answer · Option 4
Both (A) and (R) are correct but (R) is not the correct explanation of (A)
Explanation
Metal deficiency defect (like FeO) involves missing cations while electrical neutrality is maintained by higher oxidation state of remaining metal ions. Frenkel defect describes cation dislocation. Thus Assertion refers to metal deficiency defect, not Frenkel defect. Hence (A) is correct and (R) is correct statement about Frenkel defect, but R is not the correct explanation of A.
