Question

What is meant by hybridisation of atomic orbitals? Describe the shapes of $sp, sp ^2 , sp ^3$ hybrid orbitals.

Answer 1

Hybridization is defined as an intermixing of a set of atomic orbitals of slightly different energies, thereby forming a new set of orbitals having equivalent energies and shapes.
For example, one $2s-orbital$ hybridizes with two $2p-orbitals$ of carbon to form three new $sp ^2$ hybrid orbitals.
These hybrid orbitals have minimum repulsion between their electron pairs and thus, are more stable. Hybridization helps indicate the geometry of the molecule.

Shape of sp hybrid orbitals: sp hybrid orbitals have a linear shape. They are formed by the intermixing of s and porbitals as:

Shape of $sp ^2$ hybrid orbitals:

$sp ^2$ hybrid orbitals are formed as a result of the intermixing of one $s-orbital$ and two $2p-orbitals$. The hybrid orbitals are oriented in a trigonal planar arrangement as:

Shape of $sp ^3$ hybrid orbitals:
Four $sp ^3$ hybrid orbitals are formed by intermixing one $s-orbital$ with three $p-orbitals$. The four $sp ^3$ hybrid orbitals are arranged in the form of a tetrahedron as: