Correct increasing order for the wavelengths of absorption in the visible region for the complexes of ${Co}^{3 +}$ is

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

${[Co {(H_{2} O)}_{6}]}^{3 +}, {[Co (en)_{3}]}^{3 +}, {[Co {({NH}_{3})}_{6}]}^{3 +}$

${[Co {(H_{2} O)}_{6}]}^{3 +}, {[Co {({NH}_{3})}_{6}]}^{3 +}, {[Co (en)_{3}]}^{3 +}$

${[Co {({NH}_{3})}_{6}]}^{3 +}, {[Co (en)_{3}]}^{3 +}, {[Co {(H_{2} O)}_{6}]}^{3 +}$

${[Co (en)_{3}]}^{3 +}, {[Co {({NH}_{3})}_{6}]}^{3 +}, {[Co {(H_{2} O)}_{6}]}^{3 +}$

answer is D.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

The increasing order for the wavelengths of absorption in the visible region for the complexes of ${Co}^{3 +} is {[Co (en)_{3}]}^{3 +} < {[Co {({NH}_{3})}_{6}]}^{+ 3} < {[Co {(H_{2} O)}_{6}]}^{3 +} .$

The decreasing order of ligand strength is en > NH₃ > H₂O. Stronger ligand causes greater splitting between two energy levels.
The energy of light absorbed is more and the wavelength of light absorbed is less for the stronger ligand.

Watch 3-min video & get full concept clarity