Arrange the following complexes in increasing order of number of moles of silver chloride precipitated when one mole of each is reacted with excess of silver nitrate.
(A) $[Co(NH_3)_4Cl_2]Cl$
(B) $[Co(NH_3)_5Cl]Cl_2$
(C) $[Co(NH_3)_3Cl_3]$
(D) $[Co(NH_3)_6]Cl_3$
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (C), (A), (B), (D)
To find the number of moles of AgCl precipitated, we count only the ionisable Cl⁻ ions outside the coordination sphere.
- (C) [Co(NH₃)₃Cl₃] → no Cl⁻ outside → 0 mol AgCl
- (A) [Co(NH₃)₄Cl₂]Cl → 1 Cl⁻ outside → 1 mol AgCl
- (B) [Co(NH₃)₅Cl]Cl₂ → 2 Cl⁻ outside → 2 mol AgCl
- (D) [Co(NH₃)₆]Cl₃ → 3 Cl⁻ outside → 3 mol AgCl