Chemistry - f-block Question with Solution | TestHub

Lanthanoid ions with $4f^7$ configuration are : (A) ${\mathrm{Eu}}^{2+}$ (B) ${\mathrm{Gd}}^{3+}$ (C) ${\mathrm{Eu}}^{3+}$ (D) ${\mathrm{Tb}}^{3+}$ (E) ${\mathrm{Sm}}^{2+}$ Choose the correct answer from the options given below :