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.
- ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
- BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
- C(A) is correct but (R) is not correct
- D(A) is not correct but (R) is correct
Solution & Step-by-step Explanation
1. Assertion (A) is correct: Ionic solids remain neutral in Schottky defects (missing equal cations and anions) or if vacancy is compensated by change in oxidation state (Metal deficiency).2. Reason (R) is correct: In Frenkel defects, a cation moves from its normal site to an interstitial site. No ions leave the crystal, so neutrality is maintained.However, (R) is a specific example of maintaining neutrality but it does not explain why the solid is neutral when cations are missing (which refers to Schottky or non-stoichiometric vacancy defects).