Arrange the complexes `CoCl_3. 6NH_3, CoCl_3. 5NH_3, CoCl_3. 4NH_3` and `CoCl_2 . 3NH_3` in the descending order of conductivity of their aqueous solutions.

Explanation

Aqueous solutions containing one mole of `CoCl_(3).6NH_(3), CoCl_(3).5NH_(3),CoCl.4NH_(3)` and `CoCl_(3).3NH_(3)` gives respectively 4, 3, 2 and zero moles of ions. Mbr< Thus the conductivity order is `CoCl_(3).6NH_(3) gt CoCl_(3).5NH_(3) gt CoCl_(3).4NH_(3) gt CoCl_(3).3NH_(3)`.
Aqueous solution of `CoCl_(3).3NH_(3)` does not possess any ions and it is non conductor of electricity. `CoCl_(3).3NH_(3)` is a non electrolyte.