# Solve this following

Question:

Three complexes,

$\left[\mathrm{CoCl}\left(\mathrm{NH}_{3}\right)_{5}\right]^{2+}(\mathrm{I})$,

$\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{5} \mathrm{H}_{2} \mathrm{O}\right]^{3+}$ (II) and

$\left[\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{3+}$ (III)

absorb light in the visible region. The correct order of the wavelength of light absorbed by them is :

1. $(\mathrm{III})>(\mathrm{I})>(\mathrm{II})$

2. $(\mathrm{I})>(\mathrm{II})>(\mathrm{III})$

3. (II) $>$ (I) $>$ (III)

4. $(\mathrm{III})>(\mathrm{II})>(\mathrm{I})$

Correct Option: , 2

Solution: