Question

Match List-I with the List-II

List-I Tetrahedral Complex	List-II Electronic configuration
(A) TiCl4	(I) e2, t20
(B) [FeO4]2-	(II) e4, t23
(C) [FeCl4]-	(III) e0, t22
(D) [CoCl4]2-	(IV) e2, t23

Choose the correct answer from the options given below:

• A. (A)-(I), (B)-(III), (C)-(IV), (D)-(II)
• B. (A)-(IV), (B)-(III), (C)-(I), (D)-(II)
• C. (A)-(III), (B)-(IV), (C)-(II), (D)-(I)
• D. (A)-(III), (B)-(I), (C)-(IV), (D)-(II)

Answer 1

The Correct Option is D

To establish the correspondence between tetrahedral complexes in List-I and their electronic configurations in List-II, we must examine the oxidation states and electron configurations of the metal ions:

1. Titanium Tetrachloride, TiCl₄:
   • Titanium exhibits a +4 oxidation state in TiCl₄, yielding a d⁰ electron configuration.
   • Electronic configuration: e⁰, t₂⁰. (Configuration III represents the d⁰ state where unpaired electrons are initially assigned to the e orbitals).
2. Ferrate Ion, [FeO₄]^2-:
   • Iron in [FeO₄]^2- is typically in the +6 oxidation state, leading to the complete removal of 3d electrons and a vacant orbital.
   • Electronic configuration: e⁰, t₂⁰. (Configuration I aligns with vacant t₂ orbitals, with e orbitals being filled).
3. Tetrachloroferrate(III), [FeCl₄]^-:
   • In [FeCl₄]^-, iron is in the +3 oxidation state, resulting in a d⁵ electronic configuration.
   • Electronic configuration: e², t₂³. (Configuration IV corresponds to a high spin d⁵ configuration).
4. Tetrachlorocobaltate(II), [CoCl₄]^2-:
   • Cobalt in the +2 oxidation state within this complex possesses a d⁷ configuration.
   • Electronic configuration: e⁴, t₂³. (Configuration II matches a high spin d⁷ configuration, differentiating between paired and unpaired electrons).

Accordingly, the correct pairings of List-I with List-II are:

• (A) TiCl₄ - (III) e⁰, t₂⁰
• (B) [FeO₄]^2- - (I) e⁰, t₂⁰
• (C) [FeCl₄]^- - (IV) e², t₂³
• (D) [CoCl₄]^2- - (II) e⁴, t₂³

Therefore, the definitive answer is: (A)-(III), (B)-(I), (C)-(IV), (D)-(II)