Paramagnetic material

Definition

A paramagnetic material is a substance that becomes magnetized in the presence of an external magnetic field and loses its magnetism when the field is removed. This effect is due to the alignment of unpaired electron spins within the material.

5 Must Know Facts For Your Next Test

1. Paramagnetic materials have unpaired electrons which align with an external magnetic field, causing temporary magnetization.
2. When placed in a non-uniform magnetic field, paramagnetic materials are attracted to regions of higher magnetic field strength.
3. The magnetization of paramagnetic materials is proportional to the applied magnetic field and inversely proportional to the temperature (Curie's Law).
4. Examples of paramagnetic materials include aluminum, platinum, and oxygen.
5. Unlike ferromagnetic materials, paramagnetic materials do not retain any residual magnetism once the external magnetic field is removed.

Review Questions

• What causes a paramagnetic material to become magnetized in the presence of an external magnetic field?
• How does temperature affect the magnetization of paramagnetic materials according to Curie's Law?
• Can paramagnetic materials retain their magnetism once the external magnetic field is removed? Explain.

Related terms

Ferromagnetism: A phenomenon where certain materials like iron exhibit strong, permanent magnetism due to aligned atomic magnets even without an external magnetic field.

Diamagnetism: A form of magnetism where certain materials create an opposing weak magnetic field when exposed to an external magnetic field.

Curie's Law: $\text{M} = \frac{C \cdot B}{T}$; describes how the magnetization $\text{M}$ of a paramagnetic material is directly proportional to the applied magnetic field $\text{B}$ and inversely proportional to its temperature $\text{T}$.