Question

Given that the radius of $N a^{+}$ion is $0.95 \,?$ and that of $C l^{-}$ion is $1.81\,?$, hence in the close packed lattice of $Cl ^{-}$ions, $Na ^{+}$ions prefer to occupy

• A. tetrahedral site
• B. octahedral site
• C. cubic site
• D. trigonal site

Answer 1

Answer: (B)

octahedral site

Answer 2

Radius ratio, \frac{r_{+}}{r_{-}}=\frac{0.95\, ?}{1.81\, ?}=0.524$Therefore,$N a^{+}$ions prefer to occupy octahedral site$(0.414 - 0.732)$.