Chapter 4: Problem 62
Which orbital is used by oxygen atom to form a sigma bond with other oxygen atom in \(\mathrm{O}_{2}\) molecule? (1) sp hybrid orbital (2) \(\mathrm{sp}^{2}\) hybrid orbital (3) \(\mathrm{sp}^{3}\) hybrid orbital (4) pure p-orbital
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Orbital Hybridization
For instance, in an \(\text{O}_2\) molecule, each oxygen atom undergoes \(\text{sp}^2\) hybridization. This hybridization involves the combination of one \(2s\) and two \(2p\) orbitals to form three \(\text{sp}^2\) hybrid orbitals. These hybrid orbitals are then used to form stronger and more stable bonds between the atoms.
Understanding the concept of orbital hybridization can help you predict the geometry and bond angles in molecules. This concept is fundamental to mastering more complex topics in chemistry.
Sigma and Pi Bonds
Sigma (\(\text{σ}\)) Bonds:
These are the strongest type of covalent bond and are formed by the direct overlap of orbitals. The electron density in a sigma bond is concentrated along the axis connecting the two bonding nuclei. In \(\text{O}_2\), the sigma bond is formed using one of the \(\text{sp}^2\) hybrid orbitals from each oxygen atom.
Pi (\(\text{π}\)) Bonds:
These bonds are formed when parallel p-orbitals overlap sideways. In \(\text{O}_2\), after the formation of the sigma bond, each oxygen atom has an unhybridized p-orbital left, which are perpendicular to the internuclear axis. These unhybridized p-orbitals overlap side-by-side to form a pi bond. The electron density in a pi bond is concentrated above and below the plane of the nuclei.
Understanding the distinction between sigma and pi bonds is crucial for grasping the nature of multiple bonds in molecules. Sigma bonds provide the framework, while pi bonds add additional strength and rigidity.
sp2 Hybrid Orbitals
These \(\text{sp}^2\) hybrid orbitals are essential in the formation of sigma bonds. Each oxygen atom in \(\text{O}_2\) employs one of its \(\text{sp}^2\) hybrid orbitals to form a sigma bond with the other oxygen atom. The remaining two \(\text{sp}^2\) hybrid orbitals on each oxygen atom hold lone pairs of electrons, which do not participate directly in bonding but influence the molecule's shape.
The unhybridized \(2p\) orbital that remains after \(\text{sp}^2\) hybridization is used to form the pi bond. This unhybridized orbital overlaps with the corresponding unhybridized orbital from the other oxygen atom, creating the double bond characteristic of oxygen molecules.
Thus, \(\text{sp}^2\) hybridization plays a pivotal role in the structure and bonding of oxygen in the \(\text{O}_2\) molecule. It provides the necessary orbitals for both sigma and pi bonding, leading to a stable double-bonded framework.