The Lanthanoids

The oxidation state which is common for all lanthanoids is _____.

The position of inner transition elements is

The most common oxidation state of lanthanoids is

The general oxidation state of Lanthanoid series is

The pair that has similar atomic radii is:

Why ${\mathrm{Gd}}^{3+}$ is colourless?

Which of the following lanthanoids show $+2$ oxidation state besides the characteristic oxidation state $+3$ of lanthanoids?

Explain the oxidation state of lanthanoid and actinoid.

Explain the position of lanthanoids.

Give a reason why $\mathrm{Zr}\left(40\right) \& \mathrm{Hf}\left(72\right)$ have almost the same atomic radius.

Explain: The atomic radii of $5\mathrm{d}$ transition elements are very similar to $4\mathrm{d}$ transition elements.

What will be the number of unpaired electrons in $\mathrm{Gd} (\mathrm{Z}=64)$?

Write general electronic configuration of inner transition elements.

The correct increasing order of ionic radii of the following $C{e}^{3+}, L{a}^{3+}, P{m}^{3+} \mathrm{a}\mathrm{n}\mathrm{d} Y{b}^{3+}$ is