Chapter 4, Problem 4.26CP

Two electrostatic potential maps are shown, one of methyllithium (CH₃Li) and the other of chloromethane (CH₃Cl). Based on their polarity patterns, which do you think is which?

Interpretation Introduction

Interpretation:

From given electrostatic potential maps of methyllithium and chloromethane which is which has to be predicted based on polarity pattern.

Concept introduction:

The degree of electron transfer in polar covalent bond can be pictured with something called electrostatic potential maps which uses the colour to represent the electron distribution in an isolated gas-phase molecules.

In the electrostatic potential map colour of the parts are indicates given,

Yellow-green colour - nonpolar or neutral atom

Blue colour - an electron poor atom

Red colour- an electron rich atom.

Answer to Problem 4.26CP

(a) is found as chloromethane and (b) is found as methyllithium.

Explanation of Solution

Given:

Given two electrostatic potential maps are,

Figure 1

To predict: Methyllithium and chloromethane from given electrostatic potential maps

In electrostatic potential maps Lithium and Chlorine are placed at the top of each map.

Red colour area is for negatively polarized region hence which is accompanying with Chlorine.

The blue colour area is for passively polarized region hence it is accompanied with Lithium.

Thus, map (a) is for Methylchloride $\left({\text{CH}}_{\text{3}}\text{Cl}\right)$ and map (b) is for Methyllithium $\left({\text{CH}}_{\text{3}}\text{Li}\right)$.