Write a hybridization and bonding scheme for each molecule or ion. Sketch the structure, including overlapping orbitals, and label all bonds using the notation shown in Examples 10.6 and 10.7.
a. COCl₂ (carbon is the central atom)
b. BrF₅
c. XeF₂

Verified step by step guidance

1. Identify the central atom and count the number of regions of electron density around it. For COCl_2, carbon is the central atom with three regions of electron density: one double bond with oxygen and two single bonds with chlorine atoms.
2. Determine the hybridization of the central atom based on the number of regions of electron density. With three regions, the hybridization of carbon is sp^2.
3. Sketch the structure of COCl_2, showing the central carbon atom with sp^2 hybrid orbitals forming sigma bonds with the oxygen and chlorine atoms. The double bond with oxygen consists of one sigma bond and one pi bond.
4. Label the bonds: the C=O bond consists of a sigma bond (sp^2-p overlap) and a pi bond (p-p overlap), while each C-Cl bond is a sigma bond (sp^2-p overlap).
5. Draw the overlapping orbitals: show the sp^2 hybrid orbitals on carbon overlapping with the p orbitals of oxygen and chlorine, and the unhybridized p orbital on carbon overlapping with the p orbital on oxygen to form the pi bond.

Key Concepts

Hybridization

Hybridization is the process of mixing atomic orbitals to form new hybrid orbitals that can accommodate the bonding requirements of a molecule. In the case of COCl2, the central carbon atom undergoes sp2 hybridization, resulting in three equivalent hybrid orbitals that form sigma bonds with the two chlorine atoms and one oxygen atom, while the remaining p orbital can participate in pi bonding.

Bonding and Molecular Geometry

The bonding in molecules involves the formation of sigma (σ) and pi (π) bonds between atoms. In COCl2, the molecular geometry is trigonal planar due to the sp2 hybridization of carbon, which allows for 120-degree bond angles between the bonds. Understanding the geometry helps predict the physical and chemical properties of the molecule.

Orbital Overlap

Orbital overlap is a key concept in chemical bonding, where atomic orbitals from different atoms combine to form bonds. In COCl2, the overlap of the sp2 hybrid orbitals of carbon with the p orbitals of chlorine and oxygen leads to the formation of sigma bonds, while any remaining p orbitals can form pi bonds, illustrating the importance of orbital interactions in molecular structure.