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 anion is ----------- pm

Options

A. 114 pm
B. 288 pm
C. 398 pm
D. 618 pm

Answer

A

Explanation

For fcc , `r^(+) + r^(-) = (a)/(2)`
`110 + r^(-) = (500)/(2)`
`r^(-) = 144` pm