What is the Difference Between Atomic Orbital and Hybrid Orbital?

The main difference between atomic orbitals and hybrid orbitals lies in their formation and participation in bond formation. Here are the key differences:

1. Formation: Atomic orbitals are the wave functions of electrons in isolated atoms, representing the different energy levels and shapes of orbitals. In contrast, hybrid orbitals are formed by the mixing of two or more non-equivalent atomic orbitals. This process of combining the wave functions for atomic orbitals is called hybridization.
2. Shape and Energy: Hybrid orbitals have shapes and orientations that are very different from those of the atomic orbitals in isolated atoms. They also have different energies than the atomic orbitals from which they are formed.
3. Bond Formation: Hybrid orbitals normally participate in covalent sigma bond formation, whereas atomic orbitals participate in both sigma and pi bond formation. For example, in a CH4 molecule, the carbon atom forms four equivalent sp3 hybrid orbitals, which overlap with the hydrogen 1s orbitals to form sigma bonds.
4. Number of Hybrid Orbitals: The number of hybrid orbitals in a set is equal to the number of atomic orbitals that were combined. For instance, if two atomic orbitals are combined, two hybrid orbitals will be formed.
5. Unhybridized Orbitals: Unhybridized orbitals overlap to form pi bonds, while hybrid orbitals overlap to form sigma bonds.

In summary, atomic orbitals represent the wave functions of electrons in isolated atoms, while hybrid orbitals are formed by the mixing of atomic orbitals and have different shapes, energies, and roles in bond formation.

Comparative Table: Atomic Orbital vs Hybrid Orbital

The main differences between atomic orbitals and hybrid orbitals are:

• Origin: Atomic orbitals are the orbitals of an isolated atom, while hybrid orbitals are formed by combining atomic orbitals when atoms bond to form molecules.
• Shape and Energy: Hybrid orbitals have different shapes and energies than the atomic orbitals from which they are formed. All orbitals in a set of hybrid orbitals are equivalent in shape and energy.
• Bond Formation: Hybrid orbitals overlap to form σ bonds, while unhybridized orbitals overlap to form π bonds. The number of hybrid orbitals in a set is equal to the number of atomic orbitals that were combined.

Here is a table comparing atomic orbitals and hybrid orbitals: