Consider the following statements about manganate and permanganate ions. Identify the correct statements.

A. The geometry of both manganate and permanganate ions is tetrahedral.

B. The oxidation states of Mn in manganate and permanganate are +7 and +6, respectively.

C. Oxidation of Mn(II) salt by peroxodisulphate gives manganate ion as the final product.

D. Manganate ion is paramagnetic and permanganate ion is diamagnetic.

E. Acidified permanganate ion reduces oxalate, nitrite and iodide ions.

Choose the correct answer from the options given below :

Given below are two statements :

Statement I : The number of pairs, from the following, in which both the ions are coloured in aqueous solution is 3.

$$ \left[\mathrm{Sc}^{3+}, \mathrm{Ti}^{3+}\right],\left[\mathrm{Mn}^{2+}, \mathrm{Cr}^{2+}\right],\left[\mathrm{Cu}^{2+}, \mathrm{Zn}^{2+}\right] \text { and }\left[\mathrm{Ni}^{2+}, \mathrm{Ti}^{4+}\right] $$

Statement II : $\mathrm{Th}^{4+}$ is the strongest reducing agent among $\mathrm{Th}^{4+}, \mathrm{Ce}^{4+}, \mathrm{Gd}^{3+}$ and $\mathrm{Eu}^{2+}$.

In the light of the above statements, choose the correct answer from the options given below

Given below are two statements :

Statement I : The first ionization enthalpy of Cr is lower than that of Mn .

Statement II : The second and third ionization enthalpies of Cr are higher than those of Mn .

In the light of the above statements, choose the correct answer from the options given below :

On heating a mixture of common salt and $K_2Cr_2O_7$ in equal amount along with concentrated $H_2SO_4$ in a test tube, a gas is evolved. Formula of the gas evolved and oxidation state of the central metal atom in the gas respectively are: