Question

If CN- is a strong field ligand, rank the following coordination compounds in order of decreasing number of unpaired d-electrons: [Fe(CN6)]3- [Pd(CN6)]2- [Mo(CN6)]4-

Group of answer choices

[Fe(CN6)]3- > [Mo(CN6)]4- > [Pd(CN6)]2-

[Mo(CN6)]4- > [Fe(CN6)]3- > [Pd(CN6)]2-

[Pd(CN6)]2- > [Fe(CN6)]3- > [Mo(CN6)]4-

[Fe(CN6)]3- > [Pd(CN6)]2- > [Mo(CN6)]4-

[Mo(CN6)]4- > [Pd(CN6)]2- > [Fe(CN6)]3-

Answer 1

CNG is strong ligand ③ [Fe(CN) -3 = a + 6(-1) = -3 n=-3+6 = +3 n- +3 onidation State. Fe=[Ar] 3 do us? F e +3 =[Ar] 3dy So pairing takes place so Fe +3 Fet3 [Ar] ILALLA 1 Unfaired electron no caf unpaired electron 2. (2) [ pd CCN)]-2 - nt6(-1) = -2 n - 6 - -2 n = - 2+6 -- ty n = ty Paty onidation State Pd = [kg] udlo Paty = [kr] 4 do Pol+9 = [ko] 1L/1LAL No. of Unfaired electrows

3 [Mo (CN)7-4 n+ 6(-1) =-4 n - 6 - - 4 n= - 4+6 - +2 - +2 a so Mot2 onidation State mo - [ko] 4d5 551 motz [ka] udy mot2 [ko] No. of unpaired electron Compound Un paired electroy 1 O [Fe (CN)67-3 [Pd Cen), Emo (CN) - 4 [mo (CN)6]" > [Fe(CN)][td CoN), j (2) 2 Order (1) 1o) Unpaired electron