Final answer:
sp hybridization involves the mixing of one s and one p orbital to create two linearly arranged sp hybrid orbitals. This results in a molecule with a linear geometry, such as seen in the BeCl₂ molecule. The central atom in such a molecule is surrounded by two regions of valence electron density without lone pairs.
Step-by-step explanation:
sp Hybridization:
sp hybridization occurs when one s orbital mixes with one p orbital from the valence shell of an atom resulting in the formation of two sp hybrid orbitals. This mixing of orbitals creates a linear arrangement where the two sp hybrid orbitals align at 180° to each other with the nucleus at the center. Each sp orbital contains 50% s character and 50% p character. An example of sp hybridization can be seen in the beryllium atom in the gaseous BeCl₂ molecule, where the central Be atom has two covalent bonds with chlorine atoms and no lone pairs, resulting in a linear shape.
Other notable examples of sp hybridization include the carbon atoms in ethyne (HC≡CH) and the linear molecules of CO2 and HgCl₂. In these molecules, the central atom is surrounded by two regions of valence electron density, leading to the sp hybridization state. The two sp hybrid orbitals form sigma (σ) bonds with other atoms, while the unhybridized p orbitals form pi (π) bonds, maintaining the overall linear geometry.