Question

Match List-I with List-II

	List-I-Complex		List-II-CFSE
A	[Cu(NH3​)6​]2+	I	-0.6
B	[Ti(H2​O)6​]3+	II	-2.0
C	[Fe(CN)6​]3−	III	-1.2
D	[NiF6​]4-	IV	-0.4

Choose the correct answer from the options given below:

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

Answer 1

The Correct Option is B

Solution:
We need to match the complexes in List-I with their Crystal Field Stabilization Energy (CFSE) values in List-II.

Let's analyze each complex:

A. [Cu(NH₃)₆]²⁺
Cu²⁺ has a d⁹ configuration. In an octahedral field, it will have a t_2g⁶ e_g³ configuration. Due to Jahn-Teller distortion, the CFSE is not straightforward. However, for a d⁹ high spin configuration, it would be approximately -0.6Δ_o.
Therefore, A matches with I (-0.6).

B. [Ti(H₂O)₆]³⁺
Ti³⁺ has a d¹ configuration. In an octahedral field, it will have a t_2g¹ e_g⁰ configuration. The CFSE is -0.4Δ_o.
Therefore, B matches with IV (-0.4).

C. [Fe(CN)₆]^3-
Fe³⁺ has a d⁵ configuration. CN^- is a strong field ligand, so it will be a low spin complex with a t_2g⁵ e_g⁰ configuration. The CFSE is -2.0Δ_o.
Therefore, C matches with II (-2.0).

D. [NiF₆]^4-
Ni²⁺ has a d⁸ configuration. F^- is a weak field ligand, so it will be a high spin complex with a t_2g⁶ e_g² configuration. The CFSE is -1.2Δ_o.
Therefore, D matches with III (-1.2).

Matching:
A - I (-0.6)
B - IV (-0.4)
C - II (-2.0)
D - III (-1.2)

Correct Answer: A-I, B-IV, C-II, D-III