Draw an energy diagram for HCl. Predict the bond order and make a sketch of the lowest energy bonding molecular orbital.

Verified step by step guidance

1. Identify the atomic orbitals involved in the formation of HCl. Hydrogen has a 1s orbital, and chlorine has 3p orbitals that can participate in bonding.
2. Determine the type of bond formed between hydrogen and chlorine. HCl forms a sigma (σ) bond through the overlap of the hydrogen 1s orbital and one of the chlorine 3p orbitals.
3. Predict the bond order using the formula: Bond Order = (Number of bonding electrons - Number of antibonding electrons) / 2. For HCl, there are no antibonding electrons in the simplest model, so the bond order is 1.
4. Sketch the energy diagram: Place the hydrogen 1s orbital and the chlorine 3p orbital on the left and right, respectively. Show the formation of a bonding molecular orbital (σ) at a lower energy level than the original atomic orbitals.
5. Draw the lowest energy bonding molecular orbital: Represent the σ bond as an oval shape encompassing both nuclei, indicating the region of electron density where the 1s and 3p orbitals overlap.

Key Concepts

Energy Diagram

An energy diagram visually represents the energy levels of molecular orbitals in a molecule. It shows the relative energies of bonding, antibonding, and non-bonding orbitals, helping to understand the stability of the molecule. For HCl, the diagram will illustrate the interaction between the hydrogen and chlorine atomic orbitals, leading to the formation of molecular orbitals.

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. In the case of HCl, the bond order indicates the strength and stability of the H-Cl bond. A higher bond order generally correlates with a stronger bond.

Molecular Orbital Theory

Molecular Orbital Theory describes the behavior of electrons in molecules by combining atomic orbitals to form molecular orbitals. These orbitals can be bonding, antibonding, or non-bonding. For HCl, the lowest energy bonding molecular orbital is formed from the overlap of the hydrogen 1s orbital and the chlorine 3p orbital, which stabilizes the molecule and contributes to its bond formation.