Question

State the definitions of bonding, anti-bonding and nonbonding orbitals. Draw the

molecular orbitals obtained by the linear combination of two 1s orbitals. ​

Answer 1

The two available electrons (one from each H atom) in this diagram fill the bonding σ1s molecular orbital. ... A bonding molecular orbital is always lower in energy (more stable) than the component atomic orbitals, whereas an antibonding molecular orbital is always higher in energy (less stable).

Answer 2

Answer:

Bonding orbitals place most of the electron density between the nuclei of the bonded atoms.

Antibonding orbitals place most of the electron density outside the nuclei.

Explanation:

Electrons in bonding orbitals stabilize the molecule because they are between the nuclei. They also have lower energies because they are closer to the nuclei. Antibonding orbitals place less electron density between the nuclei.  The nuclear repulsions are greater, so the energy of the molecule increases. Antibonding orbitals are at higher energy levels than bonding orbitals.