The arrangement of `X^(-)` ions around `A^(+)` in solids `AX` is given in the figure (not drawn to scale). if the radius of `X^(-)` is `250` pm, the radius of `A^(+)` is

Options

A. `104p m`
B. `125p m`
C. `183p m`
D. `57p m`

Answer

1

Explanation

According to the given figure `A^(+)` is present in the octahedral void surrounding by `X^(-)` ions .The limiting radius in ocrahedral void is releated to the radius of surrounding sphere as
`r_("void")=0.414r_("sphere")`
`r_(A')=0.414r_(X^(-))`
`=0.414(250p m)`
`=1.03.5p m~~104p m`
Hence the correct option (1) is correct.