Which of the following is a negatively charged bidentate ligand?

$A$ complex compound of $Co^{3+}$ with molecular formula $CoCl_{x} \cdot yNH_3$ gives a total of $3$ ions when dissolved in water. How many $Cl^{-}$ ions satisfy both primary and secondary valencies in this complex?

Explain double salts and coordination compounds.

Assertion : $A$ chelating ligand must possess two or more lone pairs at such a distance that it may form suitable strain-free rings at the metal ion.
Reason : $H_2N-NH_2$ is a chelating ligand.

How many ions per molecule are produced in the solution when Mohr salt is dissolved in excess of water?

The complex of $Ni^{2+}$ ion and dimethylglyoxime contains $..........$ number of Hydrogen $(H)$ atoms.