Chapter 21, Problem 19Q

Interpretation Introduction

Interpretation:

The oxidation state of the metal and the formula of the complex formed has to be found for the given process.

Concept introduction:

Coordination complex:  In coordination complex there is a central metal atom which is connected by number of molecules or ions called ligands.  Ligands are the group which can donate one or more electron pairs to the central metal atom.  There are different classifications of ligand based on the charge, number of electrons donated to the central metal atoms...etc.  For example ${\text{H}}_{\text{2}}\text{O(aq)}$, carbon monoxide, ${\text{NH}}_3$ are neutral ligands.  ${\text{CN}}^{\text{-}}$, ${\text{Cl}}^{\text{-}}$  and ${\text{OH}}^{\text{-}}$ are charged ligands.

When only one pair of electrons are donated to the metal, the ligand is called monodentate.  When only two pairs of electrons are donated to the metal, the ligand is called bidentate.  When only more than two pair of electrons are donated to the metal, the ligand is called polydendate.

Spectrochemical series is the arrangement of ligands in the increasing order of field strength.  The ligands in the right side of the series will be of high strength and causes the pairing of electrons.