Question

The correct order of intensity of colors of the compounds is : 

(1) [Ni(CN)₄]^2– > [NiCl₄]^2– > [Ni(H₂O)₆]²⁺ 

(2) [Ni(H₂O)₆]²⁺ > [NiCl₄]^2– > [Ni(CN)₄]^2– 

(3) [NiCl₄]^2– > [Ni(H₂O)₆]²⁺ > [Ni(CN)₄]^2– 

(4) [NiCl₄]^2– > [Ni(CN)₄]^2– > [Ni(H₂O)₆]²⁺

Answer 1

Answer is (3) [NiCl₄]^2– > [Ni(H₂O)₆]²⁺ > [Ni(CN)₄]^2– 

Splitting energy order △_r < △₀ < △_sq

absorbed energy order  [NiCl₄]^2– > [Ni(H₂O)₆]²⁺ > [Ni(CN)₄]^2–

intensity of colour of compound  [NiCl₄]^2– > [Ni(H₂O)₆]²⁺ > [Ni(CN)₄]^2–