A solid `AB` has `NaCl` structure. If the radius of the cation `A` is `100` pm, what is the radius of anion `B`?

Explanation

`NaCl` has octahedral arrangement and thud
`(r^(+))/(r^(-))=0.414` to `0.732`
If `r^(+)=100p m,`
then `r^(-)=(100)/(0.414 " to "0.732)`
`=241.55 t o 136.61 p m`