Read the Assertion and Reason below and choose the correct option. — Solid State Chemistry Question

💡 Solution & Explanation

In NaCl, the radius ratio $\frac{r_{Na^+}}{r_{Cl^-}}$ mathematically falls in the range of 0.414 to 0.732, which dictates an octahedral coordination geometry. Consequently, the smaller $Na^+$ ions stably occupy the octahedral voids formed by the FCC lattice of the larger $Cl^-$ ions. Therefore, correct answer is A.