Identify all the correct statements for lanthanoide contraction.

(A) The covalent properties of the lanthanoide metal hydroxides increases from La to Lu.

(B) The chemical reactivity decreases from La to Lu.

(C) $\mathrm{La}(\mathrm{OH})_3$ is more basic than $\mathrm{Lu}(\mathrm{OH})_3$.

(D) Zr and Hf have about the same radius.

(E) Separation of lanthanoides from one another is easy.

On treating $\mathrm{SO}_2$ with aqueous solution of $\mathrm{KMnO}_4$, the manganese ion reduces to

The correct order of ionic radii of trivalent ions $\mathrm{Y}^{3+}, \mathrm{La}^{3+}, \mathrm{Eu}^{3+}$ and $\mathrm{Lu}^{3+}$ is $(\mathrm{Y}=39, \mathrm{La}=57, \mathrm{Eu}=63, \mathrm{Lu}=71)$

When permanganate ion is heated at 513 K , led to the formation of two manganese based products. The physical properties of the product in which manganese with the higher oxidation state than the other are