Skip to main content
Pearson+ LogoPearson+ Logo
Ch.7 - Covalent Bonding and Electron-Dot Structures
All textbooksMcMurry 8th EditionCh.7 - Covalent Bonding and Electron-Dot StructuresProblem 34
Chapter 7, Problem 34

Electrostatic potential maps of acetaldehyde (C2H4), ethane (C2H6), ethanol (C2H6O), and fluorethane (C2H5F) are shown. Which do you think is which? (a)
Electrostatic potential map of acetaldehyde, ethane, ethanol, and fluorethane for identification.
(b)
(c)
(d)

Verified step by step guidance
1
Identify the molecules: acetaldehyde (C2H4O), ethane (C2H6), ethanol (C2H6O), and fluoroethane (C2H5F).
Understand that the electrostatic potential map shows regions of electron density, with red indicating regions of high electron density (negative potential) and blue indicating regions of low electron density (positive potential).
Analyze the given electrostatic potential map: the red region suggests a highly electronegative atom or group.
Compare the structures of the molecules: acetaldehyde has a carbonyl group (C=O), ethanol has a hydroxyl group (OH), fluoroethane has a fluorine atom (F), and ethane is a simple hydrocarbon with no highly electronegative atoms.
Determine which molecule corresponds to the given map by matching the regions of high electron density (red) to the presence of electronegative atoms or groups in the molecular structures.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
3m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Electrostatic Potential Maps

Electrostatic potential maps visually represent the distribution of electron density in a molecule. Areas of high electron density appear in red, indicating regions of negative charge, while blue areas represent low electron density or positive charge. These maps help in understanding molecular polarity and reactivity, which are crucial for predicting how molecules will interact with each other.
Recommended video:
Guided course
00:34
Kinetic & Potential Energy

Molecular Structure and Functional Groups

The molecular structure of compounds, including their functional groups, significantly influences their chemical properties and behavior. For instance, acetaldehyde contains a carbonyl group, while ethanol has a hydroxyl group. Recognizing these functional groups allows for the identification of molecules based on their electrostatic potential maps, as different groups will affect electron distribution differently.
Recommended video:
Guided course
00:41
Functional Groups Example

Polarity and Intermolecular Forces

Polarity arises from the uneven distribution of electron density within a molecule, leading to partial positive and negative charges. This polarity affects intermolecular forces such as hydrogen bonding, dipole-dipole interactions, and London dispersion forces. Understanding these concepts is essential for predicting the physical properties of substances, such as boiling points and solubility, which can be inferred from their electrostatic potential maps.
Recommended video:
Guided course
01:59
Intermolecular vs Intramolecular Forces
Related Practice
Textbook Question
The following diagram shows the potential energy of two atoms as a function of internuclear distance. Match the descriptions with the indicated letter on the plot.(a) Repulsive forces are high between the two atoms. (b) The two atoms neither exert attractive nor repulsive forces on one another.(c) The attractive forces between atoms are maximized, resulting in the lowest energy state.(d) Attractive forces between atoms are present but are not at maximum strength.

Textbook Question
The following diagram shows the potential energy of two atoms as a function of internuclear distance. Which bond is the strongest? Which bond is the longest?

Textbook Question

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

(b)

Textbook Question
Characterize bonds between the two atoms as covalent or ionic.(a) Cl and F(b) Rb and F(c) Na and S (d) N and S
2
views
Textbook Question
The following ball-and-stick molecular model is a representation of thalidomide, a drug that causes birth defects when taken by expectant mothers but is valuable for its use against leprosy. The lines indicate only the connections between atoms, not whether the bonds are single, double, or triple. (Red = O, gray = C, blue = N, ivory = H). Give the formula of thalidomide, and indicate the positions of multiple bonds and lone pairs.

Textbook Question
Match the following descriptions with the type of bond (ionic, nonpolar covalent, covalent). (a) One or more electrons are transferred from a metal to a nonmetal atom.