Use molecular orbital theory to predict if each molecule or ion exists in a relatively stable form. a. F22–

Verified step by step guidance

1. Identify the total number of electrons in the molecule or ion. For F2^{2-}, each fluorine atom has 9 electrons, and the 2- charge adds 2 more electrons, giving a total of 20 electrons.
2. Write the electron configuration for the molecule using molecular orbitals. For diatomic molecules like F2^{2-}, use the order: \( \sigma_{1s}^2, \sigma^*_{1s}^2, \sigma_{2s}^2, \sigma^*_{2s}^2, \sigma_{2p_z}^2, \pi_{2p_x}^2, \pi_{2p_y}^2, \pi^*_{2p_x}^2, \pi^*_{2p_y}^2, \sigma^*_{2p_z}^2 \).
3. Fill the molecular orbitals with the 20 electrons according to the Aufbau principle, Pauli exclusion principle, and Hund's rule.
4. Calculate the bond order using the formula: \( \text{Bond Order} = \frac{(\text{Number of bonding electrons} - \text{Number of antibonding electrons})}{2} \).
5. Determine the stability of the molecule. A positive bond order indicates a stable molecule, while a bond order of zero or negative suggests instability.

Key Concepts

Molecular Orbital Theory

Molecular Orbital Theory (MOT) describes the behavior of electrons in molecules by combining atomic orbitals to form molecular orbitals. These orbitals can be bonding, antibonding, or non-bonding, and the distribution of electrons among them determines the stability and properties of the molecule. Understanding MOT is essential for predicting molecular stability and reactivity.

Bond Order

Bond order is a measure of the number of chemical bonds between a pair of atoms, calculated as the difference between the number of bonding and antibonding electrons divided by two. A higher bond order indicates a more stable molecule, while a bond order of zero suggests that the molecule is unstable and unlikely to exist. This concept is crucial for assessing the stability of the F22– ion.

Electron Configuration in Ions

The electron configuration of ions reflects the distribution of electrons in molecular orbitals after accounting for the gain or loss of electrons. For the F22– ion, two additional electrons must be considered, which will occupy the available molecular orbitals. Analyzing the resulting electron configuration helps determine the overall stability and existence of the ion.