List of top Chemistry Questions on The Lanthanoids asked in JEE Main

Number of colourless lanthanoid ions among the following is ____.
\[ \text{Eu}^{3+}, \, \text{Lu}^{3+}, \, \text{Nd}^{3+}, \, \text{La}^{3+}, \, \text{Sm}^{3+} \]

The correct order of basicity of oxides of vanadium is

The ′f′ orbitals are half and completely filled, respectively in lanthanide ions
[Given: Atomic no. Eu, 63; Sm, 62; Tm, 69; Tb, 65; Yb, 70; Dy, 66]
Which one of the lanthanoids given below is the most stable in divalent form?
The lanthanide ion that would show colour is-
The effect of lanthanoid contraction in the lanthanoid series of elements by and large means :
The pair that has similar atomic radii is :