All these structures exhibits resonance and can be represented by the following resonating structures.

More single bond character in resonance hybrid, more is the bond length. Hence the increasing bond length is

CO $$<$$ CO₂ $$<$$ CO$${_3^{2 - }}$$

Hybridisation of Br in BrO₃^– :

= $${1 \over 2}\left( {7 + 0 - 0 + 1} \right)$$ = 4

Four hybrid orbital means sp³ hybridisation.

Hybridisation of Xe in XeO₃ :

= $${1 \over 2}\left( {8 + 0 - 0 + 0} \right)$$ = 4

Four hybrid orbital means sp³ hybridisation.

Thus, both BrO₃^– and XeO₃ are sp³ hybridised with three bond pairs of electrons and one lone pair of electrons and results in trigonal pyramidal shape.

Due to sp hybridisation of N⁺, NO₂⁺ ion has linear shape.

SiCl₄, NH₄⁺, SO₄^2- and PO₄^3- ions are the examples of molecules/ions which are of AB₄ type and have tetrahedral structure. SCl₄ is AB₄(lone pair) types species. Although the arrangement of five sp³d hybrid orbitals in space is trigonal bipyramidal, due to the presense of one lone pair of electron in the basal hybrid orbital, the shape of AB₄(lone pair) species gets distorted and becomes distorted tetrahedral or see-saw.