Identify the neutral ligand from the following:

Explain the concept of Primary Valency and Secondary Valency as proposed by Alfred Werner.

In the complex $[E(en)_2(C_2O_4)]NO_2$,the oxidation state and coordination number of the element $'E'$ are respectively (where $(en)$ is ethylenediamine):

Identify a complex having a monodentate ligand from the following:

Which of the following complexes is neutral?

Identify the neutral ligand from the following.