‹ Back to the paper
Give reasons for the following.
Trivalent Lanthanoid ions such as La³⁺ (Z = 57) and Lu³⁺ (Z = 71) do not show any colour in their…
Trivalent Lanthanoid ions such as $\text{La}^{3+}$ ($Z = 57$) and $\text{Lu}^{3+}$ ($Z = 71$) do not show any colour in their solution. Give a reason.
Answer
Answer
Because $\mathrm{La^{3+}}$ ($4f^0$) and $\mathrm{Lu^{3+}}$ ($4f^{14}$) have no unpaired f electrons, so no f-f transition is possible and they are colourless.