What are the important condition for hybridisation?

Explanation

The important conditions for hybridisation are as follows:
(i) only the orbitals present in the valence shell of the atom are hybridised.
(ii) hybridised orbitals should have almost equal energy.
(iii) promotion of electrons is not essential condition in hybridisation.
(iv) in hybridisation, both half filled as well as fully filled orbitals can paricipate.