Question

iron, nickel, cobalt, and manganese are examples of _________ materials.
a. permanent
b. diamagnetic
c. paramagnetic
d. ferromagnetic

Explanation:

Identify the magnetic properties of the listed elements

Using the Ferromagnetism knowledge point

• Iron, nickel, and cobalt are classic examples of elements that exhibit strong magnetic properties and can be magnetized.
• Manganese, while antiferromagnetic in its pure ground state, is commonly grouped with these transition metals in introductory physics and chemistry when discussing materials that exhibit or contribute to strong magnetic behavior (such as in ferromagnetic alloys).
• These materials are characterized by having unpaired electrons and aligned magnetic domains, which is the defining feature of ferromagnetic substances.

Evaluate the given multiple-choice options

Using the Ferromagnetism knowledge point

• a. permanent: While these materials can be used to make permanent magnets, they are not themselves defined as "permanent materials."
• b. diamagnetic: Diamagnetic materials are weakly repelled by magnetic fields. Iron, nickel, and cobalt are strongly attracted.
• c. paramagnetic: Paramagnetic materials are weakly attracted to magnetic fields, whereas these transition metals exhibit much stronger, spontaneous magnetization.
• d. ferromagnetic: This is the correct classification for materials like iron, nickel, and cobalt that exhibit strong magnetic attraction and can maintain magnetization.

Answer:

• a. permanent
• b. diamagnetic
• c. paramagnetic
• d. ferromagnetic (Correct answer)