Question

A solid compound $XY$ has $NaCl$ structure. If the radius of the cation is $100\, pm$, the radius of the anion $(Y^-)$ will be -

• A. 165.8 pm
• B. 275.1 pm
• C. 322.5 pm
• D. 241.5 pm

Answer 1

Answer: (D)

241.5 pm

Answer 2

$\frac{r_c}{r_a} = 0.414 \; \; \Rightarrow \; r_a = \frac{100}{0.414} = 241.5 \; pm$