Mohr's salt is

Define the following terms: Homoleptic and heteroleptic complexes.

The molecular formula of a coordination complex is $CoH_{12}O_6Cl_3$. When one mole of this aqueous solution of the complex is reacted with an excess of aqueous $AgNO_3$ solution,$3$ moles of $AgCl$ are formed. What is the correct formula of the complex?

$NH_2-NH_2$ acts as a .......

According to Werner's theory of coordination compounds,which of the following statements is correct regarding valencies?

$3$ moles of a metal complex with the formula $Co(en)_2 Cl_3$ gives $3$ moles of silver chloride on treatment with an excess of silver nitrate. The secondary valency of $Co$ in the complex is $.....$ (Round off to the nearest integer).