Chapter 22, Problem 31QP

Interpretation Introduction

Interpretation:

The color of the given complex ion and its CFSE at the given wavelength are to be determined.

Concept Introduction:

Sunlight comprises all the colors. The objects reflecting all these colors appear white and the objects absorbing all these colors appear black. Any object that absorbs all the colors but reflects a particular color is said to possess that color.

The color in coordination compounds can be explained on the basis of crystal field splitting energy, which uses the expression: $\Delta E\text{(Δ)}=\text{h}\frac{\text{c}}{\lambda }$, where $\Delta E$ is the change in energy, $\text{h}$ is Planck’s constant, $\text{c}$ is the speed of light, and $\lambda$ is the wavelength of the photon.

The color of a complex compound is the same as the magnitude of the energy of a photon of visible light. The transition metal complex absorbs the visible light, which causes the electron to jump from a lower-energy $d$ orbital to a higher-energy $d$ orbital.