Chapter 7, Problem 7.12P

Interpretation Introduction

(a)

Interpretation:

The appropriate curved arrows and reaction products are to be drawn for the coordination step between ${\text{FeCl}}_{\text{3}}$ and ${\text{Cl}}^{\text{-}}$. Electron-rich and electron-poor reactant species are to be identified.

Concept introduction:

Formation of a single covalent bond is called the coordination step. It is also called Lewis acid-base reaction. A Lewis acid is an electron-pair acceptor whereas a Lewis base is an electron-pair donor. In the coordination step, the single curved arrow is drawn to represent the flow of electrons from an electron-rich site to an electron-poor site. Negatively charged species is called electron-rich, and positively charged species is called electron-poor.

Interpretation Introduction

(b)

Interpretation:

The appropriate curved arrow notation for heterolysis of the product from part (a) to regenerate ${\text{FeCl}}_{\text{3}}$ and ${\text{Cl}}^{\text{-}}$ is to be drawn.

Concept introduction:

An elementary step in which only a single bond is broken and both electrons from that bond end up on one of the atoms initially involved in the bond is called the heterolysis step. Heterolysis step is the reverse of the coordination step.