Why is O₂ paramagnetic?

O₂, or molecular oxygen, is considered paramagnetic due to the presence of unpaired electrons in its molecular structure. This property allows it to be attracted to magnetic fields.

Understanding Molecular Oxygen

Molecular oxygen consists of two oxygen atoms bonded together. The electronic configuration of each oxygen atom contributes to the overall properties of O₂.

Electron Configuration

The electron configuration of an oxygen atom is 1s² 2s² 2p⁴. When two oxygen atoms bond to form O₂, the molecular orbital theory shows that the 2p orbitals combine to form bonding and antibonding orbitals.

Unpaired Electrons

• In O₂, there are two unpaired electrons located in the antibonding π* orbitals.
• These unpaired electrons are responsible for the paramagnetic behavior.

Magnetic Properties

Paramagnetic substances have unpaired electrons, which create a net magnetic moment. When placed in a magnetic field, O₂ aligns with the field, demonstrating its attraction.

Applications of Paramagnetism

This property of O₂ is significant in various applications, including:

• Magnetic resonance imaging (MRI)
• Understanding biological processes like respiration

In summary, the paramagnetic nature of O₂ arises from its unpaired electrons, making it unique among diatomic molecules.