Describe the shapes of BF3 and BH4. Assign the hybridization of boron in these species.

(i) BH4-

Boron-hydride ion (BH4 ) is formed by the sp3 hybridization of boron orbitals. Therefore, it is a tetrahedral structure.



(ii) BF3


As a result of its small size and high electronegativity, boron tends to form monomeric covalent halides. These halides have a planar triangular geometry. This triangular shape is formed by the overlap of three sp2 hybridized orbitals of boron with the sp orbitals of 3 halogen atoms. Boron is sp2 hybridized in BF3.



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