Out of the following complex compounds, which of the compound will be having the minimum conductance in solution?

CONCEPT:

Conductance of Ionic Compounds in Solution

• The conductance of a compound in solution depends on the number of ions produced upon dissociation.
• More the number of ions, higher the conductance.
• Complex compounds can dissociate into different numbers of ions depending on their structure and coordination sphere.

EXPLANATION:

• [Co(NH₃)₃Cl₃]: This is a neutral complex where all three chlorides are coordinated to cobalt. It does not dissociate into ions. Hence, conductance is minimum.
• [Co(NH₃)₄Cl₂]Cl: This is a 1:2 electrolyte. It dissociates as:

  [Co(NH₃)₄Cl₂]Cl → [Co(NH₃)₄Cl₂]⁺ + Cl^-

  Producing 2 ions in solution.
• [Co(NH₃)₆]Cl₃: This is a 1:3 electrolyte. It dissociates as:

  [Co(NH₃)₆]Cl₃ → [Co(NH₃)₆]³⁺ + 3Cl^-

  Producing 4 ions in solution.
• [Co(NH₃)₅Cl]Cl: This is a 1:2 electrolyte. It dissociates as:

  [Co(NH₃)₅Cl]Cl → [Co(NH₃)₅Cl]⁺ + Cl^-

  Producing 2 ions in solution.

So, [Co(NH₃)₃Cl₃] produces no ions in solution and will have the minimum conductance.

Therefore, the compound with minimum conductance in solution is [Co(NH₃)₃Cl₃].