Question

draw the molecular orbital (mo) electron diagram for the he₂ molecule. be sure your diagram contains all of the electrons in the molecule, including any core electrons.

Explanation:

1. First, determine the number of electrons in He₂. Each He atom has 2 electrons, so He₂ has 4 electrons.
2. Then, consider the molecular - orbital energy levels. The lowest - energy molecular orbitals are the σ1s bonding and σ*1s antibonding orbitals.
3. Fill the electrons according to the Aufbau principle (fill lower - energy orbitals first), Pauli exclusion principle (each orbital can hold a maximum of 2 electrons with opposite spins), and Hund's rule (for degenerate orbitals, electrons are placed singly first with parallel spins). The 4 electrons will fill the σ1s and σ1s orbitals, with 2 electrons in σ1s and 2 electrons in σ1s.

Answer:

Draw a molecular - orbital diagram with an energy axis. Label two horizontal lines as σ1s (lower energy) and σ1s (higher energy). Place two electrons (represented as arrows with opposite spins) in the σ1s orbital and two electrons (represented as arrows with opposite spins) in the σ1s orbital.