Physical Properties of the Inner Transition Elements

Lanthanide contraction is caused due to:

In $\mathrm{d}$-Block when atomic size of one series are compared with those of corresponding element in other series :-
(I) Increase from the first $\left(3\mathrm{d}\right)$ to second $\left(4\mathrm{d}\right)$ series
(II) Increase from the second $\left(4\mathrm{d}\right)$ to third $\left(5\mathrm{d}\right)$ series
(III) Virtually the same as first $\left(3\mathrm{d}\right)$ and in second $\left(4\mathrm{d}\right)$ series
(IV) Virtually the same as second $\left(4\mathrm{d}\right)$ and in third $\left(5\mathrm{d}\right)$ series

The pair that has similar atomic radii is:

Lanthanoid contraction is due to:

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

The correct order of atomic radii is:

The size of Hafnium is almost similar to that of zirconium this is due to

The size of Nb is very similar to

Separation of lanthanides from their mixture is not easy because of

The lanthanoid contraction is responsible for the fact that :

The correct order of ionic radii of

Y³⁺, La³⁺, Eu³⁺ and Lu³⁺ is:

Which is the correct order of ionic sizes?) $\mathrm{A}\mathrm{t}.\mathrm{ }\mathrm{n}\mathrm{o}.\mathrm{ }:\mathrm{C}\mathrm{e}=58,\mathrm{ }\mathrm{S}\mathrm{n}=50,\mathrm{ }\mathrm{Y}\mathrm{b}=70\mathrm{ }\mathrm{a}\mathrm{n}\mathrm{d}\mathrm{ }\mathrm{L}\mathrm{u}=71)$

The trivalent ion having largest size in lanthanoid series is

The radius of ${\mathrm{L}\mathrm{a}}^{3+}$ (Atomic number of La = 57) is 1.06 Å. Which one of the following given values will be closest to the radius of ${\mathrm{L}\mathrm{u}}^{3+}$?

(Atomic number of Lu=71)

The correct order of ionic radii of ${\mathrm{Y}}^{3+},\mathrm{ }{\mathrm{L}\mathrm{a}}^{3+},\mathrm{ }{\mathrm{E}\mathrm{u}}^{3+}\mathrm{ }\mathrm{a}\mathrm{n}\mathrm{d}\mathrm{ }{\mathrm{L}\mathrm{u}}^{3+}$ is

Which one of the following pairs of elements is called 'chemical twins' because of their very similar chemical properties?

Identify the incorrect statement among the following.

Knowing that the chemistry of lanthanoids (Ln) is dominated by its +3 oxidation state, which of the following statements is incorrect?

Atomic radii of $\mathrm{T}\mathrm{i}$, $\mathrm{Z}\mathrm{r}$ and $\mathrm{H}\mathrm{f}$ vary

Incorrect statement is