Identify the number of moles of donor atoms in $2n$ moles of $SCN^{-}$.

$A$ ligand which has two different donor atoms and either of the two ligates with the central metal atom/ion in the complex is called $\qquad$

An excess of $AgNO_3$ is added to $100 \ mL$ of a $0.05 \ M$ solution of tetraaquadichloridochromium$(III)$ chloride. The number of moles of $AgCl$ precipitated will be . . . . . . $\times 10^{-3}$. (Nearest integer)

Identify the anionic complex from the following.

Which of the following statements is true about $[Cu(NH_3)_4]SO_4$?

In the complex $[E(en)_2(C_2O_4)]NO_2$,the oxidation state and coordination number of the element $'E'$ are respectively (where $(en)$ is ethylenediamine):