The complex ion $[Co(en)_2Br_2]^+$ has two optical isomers. Their correct configurations are:

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 $(2)$.

Which will give $Fe^{3+}$ ions in solution?

Among the statements $(a)-(d)$,the incorrect ones are:
$(a)$ Octahedral $Co(III)$ complexes with strong field ligands have very high magnetic moments.
$(b)$ When $\Delta_{0} < P$,the $d-$electron configuration of $Co(III)$ in an octahedral complex is $t_{2g}^{4} e_{g}^{2}$.
$(c)$ Wavelength of light absorbed by $[Co(en)_{3}]^{3+}$ is lower than that of $[CoF_{6}]^{3-}$.
$(d)$ If the $\Delta_{0}$ for an octahedral complex of $Co(III)$ is $18,000 \ cm^{-1}$,the $\Delta_{t}$ for its tetrahedral complex with the same ligand will be $16,000 \ cm^{-1}$.

Based on the provided reaction scheme,choose the incorrect statement:
$1. \text{Metal nitrate} \xrightarrow{\Delta} A + O_2$
$2. \text{Flame test of metal nitrate} \rightarrow \text{Golden Yellow Flame}$
$3. A + \text{Thiourea} \rightarrow \text{Solution } B$
$4. \text{Solution } B + FeCl_3 \rightarrow \text{Blood red colour complex}$

Match the following complexes in List-$I$ with their colors in List-$II$:

List-$I$ (Complex)	List-$II$ (Color)
$A. [Ni(en)_3]^{2+}$	$I. \text{Green}$
$B. [Ni(H_2O)_4(en)]^{2+}$	$II. \text{Blue}$
$C. [Ni(H_2O)_6]^{2+}$	$III. \text{Pale blue}$
$D. [Ni(H_2O)_2(en)_2]^{2+}$	$IV. \text{Violet}$