Chapter 9, Problem 9D.19E

(a)

Interpretation Introduction

Interpretation:

The number of unpaired electrons present in the complex ${\left[\text{Co}{\left(\text{CN}\right)}_{\text{6}}\right]}^{\text{3+}}$ has to be given.

(b)

Interpretation Introduction

Interpretation:

The type of wavelength (shorter or longer) absorbed when ammonia molecule replaces the cyanide ion has to be given.

Concept Introduction:

The crystal field splitting energy (CFSE) can be calculated using the following formula,

  $\text{CFSE=}\left(\text{-0}\text{.4p+0}\text{.6q}\right){\text{Δ}}_{\text{o}}$

Where p and q are the number of electrons in ${\text{t}}_{\text{2g}}$ and ${\text{e}}_{\text{g}}$ sets respectively.

Relation between energy and the wavelength:

The energy of a wave is directly proportional to its frequency, but inversely proportional to its wavelength.  In other words greater the energy larger will be the frequency and the shorter will be the wavelength.

  $\text{Energy}\text{α}\frac{\text{1}}{\text{wavelength}}$