Question

For the highlighted atoms, determine the hybridization and the formal charge. If an atom is formally neutral, indicate a charge of zero.

Answer 1

Concepts and reason

Use the formula for calculation of formal charge and hybridization of the central atoms in the given molecules.

Fundamentals

Formal charge is a theoretical concept of assigning charge to an atom in a molecule, assuming that electrons involved in bonding are equally shared between the atoms. This concept does not take into account the electronegativities of the atoms. The formal charges are assigned such that the molecule is overall electrically neutral.

Hybridization is the phenomenon of mixing of atomic orbitals to form hybrid orbitals. This is also a theoretical concept that explains bonding in a molecule. Hybrid orbitals are formed for better overlapping and stronger bonds and hence more stable molecule.

The given molecule is,

The formal charge of any atom is calculated using the following formula:

Formal charge on Nitrogen can be calculated as follows:

Formal charge on Boron can be calculated as follows:

The steric number for the central atom can be calculated as follows:

Here, V is the number of valence electrons on the central atom, X is the number of monovalent atoms around central atom, C is the formal positive charge on the atom, and A is the formal negative charge on the atom.

Calculate the steric number for nitrogen as follows:

Number of valence electrons on nitrogen$=5 $

Number of monovalent atoms around nitrogen$=3 $

Charge on atom

Thus, the hybridisation of nitrogen is .

Calculate the steric number for boron as follows:

Number of valence electrons on boron$=5 $

Number of monovalent atoms around boron$=3 $

Charge on atom$=-1 $

Thus, the hybridisation of boron is .

Ans:

Formal charge on N

Formal charge on B

Hybridization of nitrogen is .

Hybridization of boron is .