Q. The edge length of a face centred cubic cell of an ionic substance is 508 pm. If the radius of the cation is 110 pm, the radius of the anions is
A) 288 pm
B) 398 pm
C) 618 pm
D) 144 pm
Explanation
(d)
For fcc arrangement
$2\left( r^{+} + r^{-} \right) =$ edge length
$2\left( 110 + r^{-} \right) = 508$
So, $\ \ \ \ \ \ \ \ \ \ \ \ \ r^{-} = 114\ pm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.