The reaction of aqueous $[Ni(H_2O)_6]^{2+}$ is performed by the addition of a bidentate ligand ethane-$1,2$-diamine $(en)$. Match the following:

$[Ni(H_2O)_6]^{2+} : en$ molar ratio	Colour of the product
$A. 1:1$	$I. \text{Pale blue}$
$B. 1:2$	$II. \text{Blue/Purple}$
$C. 1:3$	$III. \text{Violet}$

The correct match is:

When potassium iodide is added to an aqueous solution of potassium ferricyanide,a reversible reaction is observed in which a complex $P$ is formed. In a strong acidic medium,the equilibrium shifts completely towards $P$. Addition of zinc chloride to $P$ in a slightly acidic medium results in a sparingly soluble complex $Q$.
$(1)$ The number of moles of potassium iodide required to produce two moles of $P$ is. . .
$(2)$ The number of zinc ions present in the molecular formula of $Q$ is. . . .
Give the answer for $(1)$ and $(2)$.

Select the correct statement$(s)$ regarding the $[Ni(DMG)_2]$ complex compound.

The volume (in $mL$) of $0.1 \ M$ $AgNO_3$ required for complete precipitation of chloride ions present in $30 \ mL$ of $0.01 \ M$ solution of $[Cr(H_2O)_5Cl]Cl_2$, as silver chloride is close to

The number of ions present in $2.0 \ L$ of a solution of $0.8 \ M \ K_4[Fe(CN)_6]$ is

Which of the following statements is correct?