Identify the highest field strength ligand from the following.

$A$ complex containing $K^{+}$,$Pt(IV)$ and $Cl^{-}$ is $100\%$ ionised giving $i = 3$. Thus,the possible complex is

The stepwise stability constants of a complex are given below. What is its overall reaction stability constant $\beta_4$ ?
$M + L \rightleftharpoons ML ; K_1 = 1.0 \times 10^4$
$ML + L \rightleftharpoons ML_2 ; K_2 = 1.0 \times 10^3$
$ML_2 + L \rightleftharpoons ML_3 ; K_3 = 1.0 \times 10^3$
$ML_3 + L \rightleftharpoons ML_4 ; K_4 = 1.0 \times 10^2$
(Overall reaction : $M + 4L \rightleftharpoons ML_4$)

The stability constants for complexes formed by a metal ion $(M^{2+})$ with ligands $NH_3$,$CN^-$,$H_2O$,and $en$ are $10^{11}$,$10^{27}$,$10^{15}$,and $10^8$ respectively. Based on these values,which of the following is correct?

What is the color of a cobalt chloride solution?

Assign $A, B, C, D$ from the given type of reaction: $Cd(CN)_2 \downarrow + 2KCN \longrightarrow K_2[Cd(CN)_4]$