Question

Which one ${\mathrm{Cu}}^{2+}$or ${\mathrm{Zn}}^{2+}$is diamagnetic and why?

Answer 1

Diamagnetic character:

1. Copper and zinc belong to d-block elements.
2. If the element has an unpaired electron in its orbital, it is said to be paramagnetic.
3. If the elements have only paired electrons in the orbitals, it is said to be diamagnetic.

Copper:

1. The atomic number of Copper is $29$.
2. Copper loses 2 electrons to form a ${\mathrm{Cu}}^{2+}$ion.
3. The electronic configuration of ${\mathrm{Cu}}^{2+}$ion is $\left[\mathrm{Ar}\right]3{\mathrm{d}}^9$.
4. There is one unpaired electron in the d-orbital. So, it is paramagnetic.

Zinc:

1. The atomic number of Zinc is $30$.
2. Copper loses 2 electrons to form a ${\mathrm{Zn}}^{2+}$ion.
3. The electronic configuration of ${\mathrm{Zn}}^{2+}$ion is $\left[\mathrm{Ar}\right]3{\mathrm{d}}^{10}$.
4. There is no unpaired electron in the d-orbital. So, it is diamagnetic.

Therefore, ${\mathrm{Zn}}^{2+}$ion is diamagnetic in nature.