Question

what is hybridisation? hybrid orbitals forms what bind? unhybridized orbitals forms what are the three types of hybridisation​

Answer 1

Hybridization was introduced to explain molecular structure when the valence bond theory failed to correctly predict them. It is experimentally observed that bond angles in organic compounds are close to 109o, 120o, or 180o. According to Valence Shell Electron Pair Repulsion (VSEPR) theory, electron pairs repel each other and the bonds and lone pairs around a central atom are generally separated by the largest possible angles.

Answer 2

In chemistry, orbital hybridisation (or hybridization) is the concept of mixing atomic orbitals into new hybrid orbitals (with different energies, shapes, etc., than the component atomic orbitals) suitable for the pairing of electrons to form chemical bonds in valence bond theory.

Single covalent bonds that form between nuclei are created from the "head-to-head" overlap of orbitals and are called sigma (s) bonds. This overlap may involve s-s, s-p, s-d or even p-d orbitals. Another type of bond, a pi (p) bond is formed when two p orbitals overlap.

The unhybridized p atomic orbitals are used to form π bonds. Two unhybridized p atomic orbitals each from a different atom overlap side to side, resulting in a shared electron pair occupying the space above and below the line joining the atoms (the internuclear axis).

Based on the types of orbitals involved in mixing, the hybridization can be classified as sp3, sp2, sp, sp3d, sp3d2, sp3d3.