Simplified absorption spectra of three complexes ((i),
Question:

Simplified absorption spectra of three complexes ((i), (ii) and (iii)) of $\mathrm{M}^{\mathrm{nt}}$ ion are provided below; their $\lambda_{\max }$

values are marked as $\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$ respectively. The correct match between the complexes and their $\lambda_{\max }$

values is :

(i) $\left[\mathrm{M}(\mathrm{NCS})_{6}\right]^{(-6+\mathrm{n})}$

(ii) $\left[\mathrm{MF}_{6}\right]^{(-6+\mathrm{n})}$

(iii) $\left[\mathrm{M}\left(\mathrm{NH}_{3}\right)_{6}\right]^{\mathrm{n}+}$

1. $\mathrm{A}-(\mathrm{ii}), \mathrm{B}-(\mathrm{i}), \mathrm{C}-(\mathrm{iii})$

2. $A-(i i i), B-(i), C-(i i)$

3. $\mathrm{A}-(\mathrm{ii}), \mathrm{B}-(\mathrm{iii}), \mathrm{C}-(\mathrm{i})$

4. $\mathrm{A}-(\mathrm{i}), \mathrm{B}-(\mathrm{ii}), \mathrm{C}-(\mathrm{iii})$

Correct Option: , 2

Solution:

Strength of ligand $\mathrm{F}<\mathrm{NCS}^{-}<\mathrm{NH}_{3}$

As given in graph : $\mathrm{A}<\mathrm{B}<\mathrm{C} \quad\left(\lambda_{\max }\right)$

$\therefore$ Correct matching is $\mathrm{A}$-(iii), $\mathrm{B}$-(i), $\mathrm{C}$-(ii)

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