Question

Which one out of the following materials is \(\textit{not}\) paramagnetic
 

• A. Aluminium
• B. Sodium Chloride
• C. Calcium
• D. Copper Chloride

Hint:

Paramagnetic substances have unpaired electrons. Ionic compounds like NaCl, with fully filled orbitals, are typically diamagnetic.

Answer 1

The Correct Option is B

A material is said to be paramagnetic if it has unpaired electrons in its atomic or molecular structure, which causes it to be attracted to an external magnetic field. Let's examine each option to determine which one is not paramagnetic:

1. Aluminium: Aluminium has unpaired electrons in its atomic structure, making it paramagnetic.
2. Sodium Chloride: Sodium chloride is an ionic compound made up of Na⁺ and Cl^- ions. Both ions have a full set of electrons in their shells, meaning there are no unpaired electrons present. Therefore, sodium chloride is not paramagnetic; it is diamagnetic.
3. Calcium: Although elemental calcium is not strongly magnetic, it has some unpaired electrons making it weakly paramagnetic.
4. Copper Chloride: Copper chloride, specifically in its anhydrous form (CuCl₂), contains copper ions with unpaired electrons, contributing to its paramagnetic nature.

Conclusively, the material that is not paramagnetic is Sodium Chloride.