$\Delta_{O} \propto \frac{1}{\lambda}$ $\therefore$ The absorb wave length order is $\left[Co(CN)_6\right]^{3-}<\left[Co\left(NH_3\right)_6\right

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

${\left[ Co ( CN )_6\right]^{3-}<\left[ Co \left( NH _3\right)_6\right]^{3+}<\left[ Co \left( NH _3\right)_5\left( H _2 O \right)\right]^{3+}<\left[ Co \left( NH _3\right)_5( Cl )\right]^{2+}}$

$\Delta_{O} \propto \frac{1}{\lambda}$ $\therefore$ The absorb wave length order is $\left[Co(CN)_6\right]^{3-}<\left[Co\left(NH_3\right)_6\right]^{3+} < \left[Co\left(NH_3\right)_5 H_2 O\right]^{3+}<\left[Co\left(NH_3\right)_5 Cl\right]^{2+}$

Class 11 Chemistry Data Entry - Chemistry Level 0 of all question bank

The correct order of the wavelength maxima of the absorption band in the ultraviolet-visible region for the given complexes is

IIT 2025 All IIT

A
${\left[ Co \left( NH _3\right)_5( Cl )\right]^{2+}<\left[ Co \left( NH _3\right)_5\left( H _2 O \right)\right]^{3+}<\left[ Co \left( NH _3\right)_6\right]^{3+}<\left[ Co ( CN )_6\right]^{3-}}$
B
${\left[ Co ( CN )_6\right]^{3-}<\left[ Co \left( NH _3\right)_6\right]^{3+}<\left[ Co \left( NH _3\right)_5\left( H _2 O \right)\right]^{3+}<\left[ Co \left( NH _3\right)_5( Cl )\right]^{2+}}$
C
${\left[ Co ( CN )_6\right]^{3-}<\left[ Co \left( NH _3\right)_5( Cl )\right]^{2+}<\left[ Co \left( NH _3\right)_5\left( H _2 O \right)\right]^{3+}<\left[ Co \left( NH _3\right)_6\right]^{3+}}$
D
${\left[ Co \left( NH _3\right)_6\right]^{3+}<\left[ Co ( CN )_6\right]^{3-}<\left[ Co \left( NH _3\right)_5( Cl )\right]^{2+}<\left[ Co \left( NH _3\right)_5\left( H _2 O \right)\right]^{3+}}$