Which of the following statement is `//` are true ?

Options

A. Basac on VSEPR theory, the number of 90 degree `F-Br` angles in `BrF_(5)` is four.
B. Molecular geometries of both `(CH_(3))_(3)N` and `(SiH_(3))_(3)` are trigonal planar.
C. The `C-C` bond length in `C_(2)` is bigger than `O-O` bond length `O_(2)`.
D. For ozone molecule, one oxygen `-` oxygen bond is stronger than the other oxygen `-` oxygen bond.

Answer

3

Explanation

`(1)` The spatial arrangement of six electron clouds ( five bond pairs and one lone pair) round the central `Br-` atom is octahedral. Due to the presence of one lone pair of electrons in the axial hybrid orbital, the shape of `BrF_(5)` gets distorted and becomes square pyramidal. Base `F-` atoms are slightly displaced upwards from the base of the square pyramid.

`{:(Br-F(b),"distance"=1.79 Å),(Br-F(a),"distance"=1.68 Å),(F(b)-Br-F(b),"angle"=89^(@) 48'),(F(b)-Br-F(a),"angle"=86^(@) 30'),(F(b)-Br-e,"angle"=93^(@)30'):}`
`(2)` Molecular geometries of `(CH_(3))_(3)N` and `(SiH_(3))_(3)N` are trigonal pyramidal and trigonal planar respectively. `(SiH_(3))_(3)N` involves the `p pi-dpi` delocalisation of lone pair of electrons present on `N` atom.
`(3) C_(2)=131 p m, O_(2)=123p m`
both bonds are equally stronger due to resonance.