Chapter 24: Problem 70
Draw molecular orbital energy level diagrams for \(\mathrm{O}_{2}\) \(\mathrm{O}_{2}^{-},\) and \(\mathrm{O}_{2}^{2-}\)
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Molecular Orbital Diagrams
This progression from lower energy bonding orbitals to higher energy anti-bonding orbitals helps determine the molecule's stability, bonding order, and magnetic properties. Understanding this concept is fundamental when predicting how changes in electron counts affect molecular properties such as bond length and strength.
Diatomic Molecules
When analyzing diatomic molecules, understand that their behavior and properties are significantly influenced by such factors as
- The types of orbitals involved
- The number of available electrons
- The energy levels of their molecular orbitals
The simplest diatomic molecules, such as hydrogen (H₂) or oxygen \((O_2)\), often serve as a foundation for understanding more complex molecular structures.
Oxygen Molecule
In the ground state, these orbitals fill in a way that contains non-bonding, bonding, and anti-bonding electrons, resulting in the molecule's paramagnetic character due to the two unpaired electrons found in the \(π^*\) orbitals.
When extra electrons are added, as in the \(O_2^{-}\) or \(O_2^{2-}\) ions, they occupy the \(π^*\) orbitals, altering molecular properties like magnetism and bond order. Understanding the electron distribution in \(O_2\) through an MO diagram clarifies several unique features of oxygen, including its ability to form various oxidation states and its role in combustion and respiration.
Electron Configuration
- Neutral \(O_2\) has a configuration of \(σ_{1s}^2 σ^*_{1s}^2 σ_{2s}^2 σ^*_{2s}^2 σ_{2p_z}^2 π_{2p_x}^2 π_{2p_y}^2 π^*_{2p_x}^1 π^*_{2p_y}^1\)
- For \(O_2^{-}\), one additional electron means one of the \(π^*\) orbitals gains another electron, changing the electron distribution.
- In \(O_2^{2-}\), the extra two electrons fully pair up in the \(π^*\) orbitals, rendering the molecule diamagnetic.