Question

Liquid oxygen and liquid nitrogen are allowed to flow between the poles of an electromagnet.
Choose the correct observation:

• A. Both will be attracted, but to the opposite poles
• B. Both will be attracted, but to the same poles
• C. Liquid $O_2$ will be attracted, but liquid $N_2$ will be unaffected
• D. Liquid $O_2$ will be attracted, but liquid $N_2$ will be repelled

Answer 1

The correct option is D Liquid $O_2$ will be attracted, but liquid $N_2$ will be repelled

In $O_2$ molecule, the antibonding ${\pi }^{\ast }2p_x$ and ${\pi }^{\ast }2p_y$ orbitals are singly occupied and hence it is paramagnetic in nature and is attracted to the electromagnet.

Whereas in $N_2$, the $\sigma 2p_z$ is fully occupied and hence $N_2$ is diamagnetic and is repelled by the electromagnet.