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)

Calculate the overall complex dissociation equilibrium constant for the $Cu(NH_3)_4^{2+}$ ion,given that $\beta_4$ for this complex is $2.1 \times 10^{13}$.

Which of the following complexes represents maximum stability?

Which of the following correctly represents copper sulphate pentahydrate?

$A$ first row transition metal $(M)$ does not liberate $H_{2}$ gas from dilute $HCl$. $1 \ mol$ of aqueous solution of $MSO_{4}$ is treated with excess of aqueous $KCN$ and then $H_{2}S_{(g)}$ is passed through the solution. The amount of $MS$ (metal sulphide) formed from the above reaction is . . . . . . $mol$.

Which of the following complex ions is most stable?