One mole of an octahedral compound [MCl₃E₂] is reacted with AgNO₃ to give 1 mol AgCl which means the complex exists as [MCl₂E₂]Cl. The formation of AgCl is due to the reaction of AgNO₃ with Cl^- giving AgCl. One mole of AgCl is obtained, which means only one chlorine is free. Hence, the complex has to be [MCl₂E₂]Cl. For an octahedral complex, the coordination number must be 6. Now the denticity of Cl^- is 1 and two Cl^- are present so two valencies are satisfied by chlorine. To make the coordination number 6 ligand E has to be bidentate.

Therefore, the denticity of E must be 2.