MCQ
Which of the following becomes paramagnetic on heating?
- A$\text{MnO}$
- B$\mathrm{Fe_3O_4}$
- C$\mathrm{ZnFe_2O_4}$
- ✓$B$ and $C$ both
✓
Answer
Correct option: D.
$B$ and $C$ both
Ferrimagnetic change their nature on heating and become paramagnetic
eg. $\mathrm{Fe}_3 \mathrm{O}_4, \mathrm{ZnFe}_2 \mathrm{O}_4, \mathrm{MgFe}_2 \mathrm{O}_4$
eg. $\mathrm{Fe}_3 \mathrm{O}_4, \mathrm{ZnFe}_2 \mathrm{O}_4, \mathrm{MgFe}_2 \mathrm{O}_4$
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