The aqueous solution of $CuCrO_4$ is green because it contains

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 $(2)$.

$1\,L, 0.02\,M$ solution of $[Co(NH_3)_5SO_4]Br$ is mixed with $1\,L, 0.02\,M$ solution of $[Co(NH_3)_5Br]SO_4$. The resulting solution is divided into two equal parts $(X)$ and treated with excess $AgNO_3$ solution and $BaCl_2$ solution respectively as shown below:
$1\,L$ Solution $(X) + AgNO_3$ solution (excess) $\rightarrow Y$
$1\,L$ Solution $(X) + BaCl_2$ solution (excess) $\rightarrow Z$
The number of moles of $Y$ and $Z$ respectively are:

Given below are two statements:
Statement $I$ : Dimethyl glyoxime forms a six-membered covalent chelate when treated with $NiCl_2$ solution in presence of $NH_4OH$.
Statement $II$ : Prussian blue precipitate contains iron both in $(+2)$ and $(+3)$ oxidation states.
In the light of the above statements,choose the most appropriate answer from the options given below:

The ammonia prepared by treating ammonium sulphate with calcium hydroxide is completely used by $NiCl_2 \cdot 6H_2O$ to form a stable coordination compound. Assume that both the reactions are $100 \%$ complete. If $1584 \ g$ of ammonium sulphate and $952 \ g$ of $NiCl_2 \cdot 6H_2O$ are used in the preparation,the combined weight (in grams) of gypsum and the nickel-ammonia coordination compound thus produced is $\qquad$ (Atomic weights in $g \ mol^{-1}: H=1, N=14, O=16, S=32, Cl=35.5, Ca=40, Ni=59$)

List-$I$ contains metal species and List-$II$ contains their properties.

List-$I$	List-$II$
$I$. $[Cr(CN)_6]^{4-}$	$P$. $t_{2g}$ orbitals contain $4$ electrons
$II$. $[RuCl_6]^{2-}$	$Q$. $\mu$ (spin-only) $= 4.9 \ BM$
$III$. $[Cr(H_2O)_6]^{2+}$	$R$. low spin complex ion
$IV$. $[Fe(H_2O)_6]^{2+}$	$S$. metal ion in $4+$ oxidation state
	$T$. $d^4$ species

[Given: Atomic number of $Cr = 24, Ru = 44, Fe = 26$] Match each metal species in List-$I$ with their properties in List-$II$,and choose the correct option.