Which of the following complexes represents maximum stability?

If $NaOH$ is added to an aqueous solution of zinc ions,a white precipitate appears and on adding excess $NaOH$,the precipitate dissolves. In this solution,zinc exists in the

The overall stability constant of the complex ion $[Cu(NH_3)_4]^{2+}$ is $2.1 \times 10^{13}$. The overall dissociation constant is $y \times 10^{-14}$. Then $y$ is ....... .(Nearest integer)

Assign $A, B, C, D$ from the given type of reaction: $AgI \downarrow + 2Na_2S_2O_3 \longrightarrow Na_3[Ag(S_2O_3)_2] + NaI$

Cobalt$(III)$ chloride forms a green coloured complex '$X$' with $NH_3$. The number of moles of $AgCl$ formed when an excess of $AgNO_3$ solution is added to $100 \ mL$ of a $1 \ M$ solution of '$X$' is:

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?