what is hybridization? explain the bond formation of BF3 using the concept of hybridization?
The Correct Answer and Explanation is:
Hybridization and Bond Formation in BF₃ (Boron Trifluoride)
Hybridization is a concept in chemistry where atomic orbitals mix to form new, equivalent hybrid orbitals. This theory helps explain the shape and bonding of molecules that cannot be described using only the original atomic orbitals (s, p, d, f). These hybrid orbitals have specific orientations in space, allowing for better overlap with other orbitals and thus more stable bonds.
In the case of boron trifluoride (BF₃), hybridization explains how boron forms three equivalent bonds with fluorine atoms despite having only three valence electrons and incomplete octet.
Boron (B) has the electron configuration 1s² 2s² 2p¹. In the ground state, it has two electrons in the 2s orbital and one in the 2p orbital. To form three bonds, boron promotes one of the 2s electrons to the empty 2p orbital, resulting in three unpaired electrons in the 2s and 2p orbitals. Then, one 2s orbital and two 2p orbitals hybridize to form three equivalent sp² hybrid orbitals.
Each of these three sp² hybrid orbitals overlaps with the 2p orbital of a fluorine atom to form a σ (sigma) bond, creating a trigonal planar structure with bond angles of approximately 120°.
The boron atom in BF₃ is thus sp² hybridized, and the molecule has a trigonal planar geometry. Each B–F bond is a single covalent bond formed by the overlap of a boron sp² hybrid orbital with a fluorine 2p orbital.
Notably, BF₃ is an electron-deficient molecule because boron has only six electrons in its valence shell after bonding. This makes it a Lewis acid, capable of accepting a pair of electrons from a donor (Lewis base) to complete its octet.
In summary, hybridization helps explain the equal bond lengths, angles, and geometry in BF₃ by showing how boron’s orbitals rearrange to form three identical bonding orbitals.
