Final answer:
The "sp" hybrid orbitals are formed when one s orbital and one p orbital from an atom's valence shell mix to create two hybrid orbitals that are linearly arranged at 180° from each other. These orbitals have both s and p character and are involved in forming σ bonds with other atom's orbitals.
Step-by-step explanation:
Understanding "sp" Hybrid Orbitals
The concept of "sp" hybrid orbitals originates from the orbital hybridization theory in chemistry. When we talk about hybridization, we refer to the process in which atomic orbitals mix to form new hybrid orbitals that have different energies and shapes than the original atomic orbitals. Specifically, sp hybridization involves the combination of one s orbital and one p orbital from the valence shell of an atom to create two hybrid orbitals.
This process results in two sp hybrid orbitals that have 50% s-character and 50% p-character. Each of these orbitals consists of two lobes, a larger one, and a smaller one, with the nucleus of the atom located between them. These lobes are arranged linearly, at 180° with respect to each other. In the case of molecules like BeCl₂, these hybrid orbitals will overlap with the orbitals of other atoms (like chlorine) to form sigma bonds (σ bonds).
The sp hybridization process is important in explaining the geometry and bonding properties of molecules with double or triple bonds where the remaining p orbitals (not involved in the hybridization) can form pi bonds (π bonds).