`CsCl`crystallizes in body centred cubic lattice. If `'a'` is its edge length then which of the following expressions is correct ?

Options

A. `r_(Cs) + r_(Cl^(-)) = 3a`
B. `r_(Cs) + r_(Cl^(-) ) = (3a)/(2)`
C. `r_(Cs) + r_(Cl^(-)) = (sqrt3)/(2) a`
D. `r_(Cs) + r_(Cl^(-)) = sqrt3a`

Answer

C

Explanation

Relation between radius of cation , anion and edge length of the cube
`2r_(Cs^+) + 2r_(Cl^-) = sqrt3a`
`r_(Cs^+) + r_(Cl^-) = (sqrt3a)/(2)`