(a) Account for the following :
(i) Ozone is thermodynamically unstable.
(ii) Solid `PCl_(5)` is ionic in nature.
(iii) Fluorine forms only one oxoacid HOF.
(b) Draw the structure of
(i) `BrF_(5)`
(ii) `XeF_(4)`

Explanation

(i) Ozone is thermodynamically unstable since it decomposes into oxygen results in liberation of heat.
`underset("Ozone")(O_(2)(g))rarr underset("Dioxygen")(O_(2)(g))+underset("Atomic Oxygen")(O(g))`
(ii) In solid state, `PCl_(5)` exist as `[PCl_(4)]+[PCl_(6)]^(-) 2PCl_(5) rarr[PCl_(4)]^(+)[PCl_(6)]^(-)`
Hence, ionic in nature.
(iii) Due to small size and high electronegativity of fluorine, it forms only one oxoacid HOF.