If the radius of `Br^(-)` ion is 0.182 nn, how large can a cation be fit in its tetrahedral holes ?

Answer

`< 7.53 xx 10^(-2) nm`

Explanation

For a cation to fit into a tetrahedral hole
`(r_+)/(r_(-)) < 0.414`
or ` r_(+) < 0.414 xx r_(-)`
`< 0.414 xx 0.182 nm`
`r_(+) < 7.53 xx 10^(-2) nm`