General Chemistry
Principles and Modern Applications
Petrucci • Harwood • Herring
8th Edition
Chapter 13: Liquids, Solids and
Intermolecular Forces
Philip Dutton
University of Windsor, Canada
N9B 3P4
Prentice-Hall © 2002
(modified 2003 by Dr. Paul Root and 2005 by Dr. David Tramontozzi)
Contents
13-1
13-2
13-3
13-4
13-5
13-6
13-7
13-8
13-8
Intermolecular Forces and some Properties of Liquids
Vaporization of Liquids: Vapor Pressure
Some Properties of Solids
Phase Diagrams
Van der Waals Forces
Hydrogen Bonding
Chemical Bonds as Intermolecular Forces
Crystal structures
Energy Changes in the Formation of Ionic Crystals
Focus on Liquid Crystals
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General Chemistry: Chapter 13
13-7 Chemical Bonds as
Intermolecular Forces
Two allotropes of pure carbon. Examples of network covalent solids
GRAPHITE
DIAMOND
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General Chemistry: Chapter 13
Other Carbon Allotropes
FULLERENES (C60)
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General Chemistry: Chapter 13
NANOTUBES
Interionic Forces
The attractive force between a pair of opposite ions increases
with increased charge and decreased ionic sizes.
Lattice Energy is the energy given off when separated gaseous
ions come together to form one mole of an ionic solid
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General Chemistry: Chapter 13
13-8 Crystal Structures
Regular pattern repeats itself
to generate the entire crystal .
The repeat unit in a crystal
lattice is called the UNIT
CELL.
The entire lattice can be
generated by simple
displacements of the unit cell.
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General Chemistry: Chapter 13
Unit Cells in the Cubic Crystal System
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General Chemistry: Chapter 13
Holes in Crystals
Tetrahedral holes fall directly over spheres.
Octahedral holes fall directly over holes
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General Chemistry: Chapter 13
Hexagonal Close Packed (hcp)
HEXAGONAL CLOSEST PACKED
All tetrahedral holes are covered.
Layer C is identical to layer A
CUBIC CLOSEST PACKED
All octahedral holes are covered.
Layer D is identical to layer A
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General Chemistry: Chapter 13
Coordination Number
The number of atoms with which a
given atom is in direct contact
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General Chemistry: Chapter 13
Counting Cell Occupancy
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General Chemistry: Chapter 13
X-Ray Diffraction
Need to use much shorter wavelength than
visible light to interact with atoms
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General Chemistry: Chapter 13
X-Ray Diffraction
Using the Bragg equation nλ = 2dsinθ we can calculate the
spacing between planes of atoms, ions or molecules and therefore
determine the crystal structure.
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General Chemistry: Chapter 13
Holes in Crystals
Summary of ionic ratios
0.225 < r+ /R- < 0.414
Tetrahedral hole of fcc
anions occupied by cation
0.414 < r+ /R- < 0.732
Octahedral hole of fcc
anions occupied by cation
0.732 < r+ /RCubic hole of cubic anions
occupied by cation
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General Chemistry: Chapter 13
Cesium Chloride
Ratio of cation to anion is 0.934 (169/181). Cesium
occupies cubic hole made by anions
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General Chemistry: Chapter 13
Sodium Chloride
Ratio of cation to anion is 0.55 (99/181). Sodium occupies
octahedral hole made by anions
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General Chemistry: Chapter 13
Atomic Radii from Crystal Structures
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General Chemistry: Chapter 13
Other unit cells of greater complexity
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General Chemistry: Chapter 13
13-9 Energy Changes in the Formation of
Ionic Crystals
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General Chemistry: Chapter 13
Chapter 13 Questions
1, 3, 4, 13,
24, 26, 31,
45, 52, 61,
94, 107
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General Chemistry: Chapter 13
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