Which of the following is a $\pi$-acid ligand?

How many $EDTA$ (ethylenediaminetetraacetic acid) molecules are required to make an octahedral complex with a $Ca^{2+}$ ion?

Which of the following ligands can form a chelate?

How many ions per molecule are produced from the complex $[Co(NH_3)_6]Cl_2$ in solution?

One mole of the coordination compound $Co(NH_3)_5Cl_3$ gives $3$ moles of ions upon dissolution in water. Furthermore,one mole of this complex reacts with $2$ moles of $AgNO_3$ solution to produce $2$ moles of $AgCl(s)$. The structure of the complex is:

Define the following terms: Homoleptic and heteroleptic complexes.