IONIC BONDS:
OBSERVING CHARGED OBJECTS
Get 2 balloons & rub both of them on your hair. Let go of the
balloons & walk away from them.
1. What happens to the balloons?
The balloons move apart, or repel each other.
2. Offer an explanation for the behavior of the balloons.
Rubbing caused the balloons to gain a similar charge.
3. Predict which subatomic particle is most likely to be transferred
during the rubbing. Give a reason for your choice.
Electrons are most likely to be transferred based on their
location in atoms and their motion.
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Chapter 6: Chemical Bonds
1
IONIC BONDS:
OBSERVING CHARGED OBJECTS
Get 2 balloons & rub both of them on your hair. Let go of the
balloons & walk away from them.
1. What happens to the balloons?
balloons move apart, or repel each other.
2. Offer an explanation for the behavior of the balloons.
Rubbing caused the balloons to gain a similar charge.
3. Predict which subatomic particle is most likely to be transferred
during the rubbing. Give a reason for your choice.
Electrons are most likely to be transferred based on their
location in atoms and their motion.
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Chapter 6: Chemical Bonds
2
CHAPTER 6:
CHEMICAL BONDS
Li
C
F
Ne
6.1 IONIC BONDING
6.2 COVALENT BONDING
6.3 NAMING COMPOUNDS AND WRITING FORMULAS
6.4 THE STRUCTURE OF METALS
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Chapter 6: Chemical Bonds
3
6.1 ORGANIZING THE ELEMENTS
n 
Vocabulary: electron dot diagram, ion, anion, cation, chemical
bond, ionic bond, chemical formula, crystals
n 
Objectives:
n 
n 
n 
n 
n 
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Recognize stable electron configurations.
Predict an element s chemical properties using
number of valence electrons & electron dot diagrams.
Describe how an ionic bond forms and how ionization
energy affects the process.
Predict the composition of an ionic compound from its
chemical formula.
Relate the properties of ionic compounds to the
structure of crystal lattices.
Chapter 6: Chemical Bonds
4
8A
IONIC BONDING
n 
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6A
7A
Why is argon very inactive
yet oxygen is highly reactive?
Chapter 6: Chemical Bonds
5
Group 8A
STABLE ELECTRON CONFIGURATIONS
n 
Chemical properties depend on # of
valence electrons
n 
When is an atom stable & least likely
to react?
when the highest occupied energy
level of an atom is filled with electrons
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Chapter 6: Chemical Bonds
6
electron dot diagram - model of an atom in which
each dot represents a valence electron
Valence
electrons
He
Symbol
represents - nucleus & all
other electrons in atom
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Chapter 6: Chemical Bonds
7
ELECTRON DOT DIAGRAMS FOR
SOME GROUP A ELEMENTS
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Chapter 6: Chemical Bonds
8
IONIC BONDS:
TRANSFER OF ELECTRONS - CHLORINE
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Chapter 6: Chemical Bonds
9
IONIC BONDS:
TRANSFER OF ELECTRONS - SODIUM
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Chapter 6: Chemical Bonds
10
IONIC BONDS:
TRANSFER OF ELECTRONS
n 
What happens at the atomic level when sodium
reacts with chlorine?
Na + Cl
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Chapter 6: Chemical Bonds
11
IONIC BONDS:
TRANSFER OF ELECTRONS
n 
What happens at the atomic level when sodium
reacts with chlorine?
n  electron transferred from sodium atom to
chlorine atom
Na + Cl
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Chapter 6: Chemical Bonds
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IONIC BONDS:
TRANSFER OF ELECTRONS
n 
What happens at the atomic level when sodium
reacts with chlorine?
n  electron transferred from sodium atom to
chlorine atom
n  atoms ends up with more stable electron
arrangement
Na + Cl
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Na+ Cl Chapter 6: Chemical Bonds
13
IONIC BONDS:
TRANSFER OF ELECTRONS
Na + Cl
Na+ Cl -
http://www.youtube.com/watch?v=Mx5JJWI2aaw
+
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Chapter 6: Chemical Bonds
14
IONIC BONDS: FORMATION OF IONS
n 
ion - atom that has net positive or negative
electric charge
n 
Charge represented by + or – sign
Na + Cl
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Na+ + Cl -
Chapter 6: Chemical Bonds
15
IONIC BONDS: FORMATION OF IONS
Sodium
Chlorine
Na
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Cl
Chapter 6: Chemical Bonds
16
IONIC BONDS: FORMATION OF IONS
Sodium
Sodium
Ion
Chloride
ChlorineIon
Na 1+
Cl1-
1+
1-
cation - ion with
positive charge
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anion - ion with
negative charge
Chapter 6: Chemical Bonds
17
IONIC BONDS: FORMATION OF IONS
Sodium Ion Sodium Chloride Chloride Ion
Na 1+
Cl1-
1+
1-
cation - ion with
positive charge
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anion - ion with
negative charge
Chapter 6: Chemical Bonds
18
CATIONS vs. ANIONS
loses
electrons
to
form a
cation (+)
gains
electrons
from
form an
anion (-)
ATOM
(neutral)
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Chapter 6: Chemical Bonds
19
FORMATION OF IONIC BONDS
n 
chemical bond - force that holds atoms or ions
together as a unit
n 
ionic bond - force that holds cations and
anions together. Forms when electrons are
transferred from one atom to another
http://www.absorblearning.com/media/attachment.action?quick=sn&att=2052
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Chapter 6: Chemical Bonds
20
IONIC BONDS:
IONIZATION ENERGY (Page 160)
n 
atom absorbs energy, electron can move to a
higher energy level
n 
cations form when electrons gain enough
energy to overcome attraction of protons in
nucleus & escape from atoms
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Chapter 6: Chemical Bonds
21
IONIC BONDS:
IONIZATION ENERGY (Page 160)
n 
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ionization energy - amount of energy used to
remove electron
n 
varies from element to element
n 
lower the ionization energy, the easier it is
to remove an electron from an atom
Chapter 6: Chemical Bonds
22
IONIC BONDS:
IONIZATION ENERGY (Page 160)
n 
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ionization energies tend to
n  increase from left to right across a period
n  decrease from top to bottom of a group
Chapter 6: Chemical Bonds
23
IONIC COMPOUNDS
n 
Ionic compounds can be represented by
chemical formulas.
n 
Chemical formula - notation that shows what
1. elements a compound contains
2. ratio of atoms or ions of these elements in
the compound
n 
e.g. chemical formula for sodium chloride is
NaCl (1 Na ion for every 1 Cl ion)
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Chapter 6: Chemical Bonds
24
Water
Molecules
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Chapter 6: Chemical Bonds
25
IONIC COMPOUNDS
n 
Based on the diagram, what would the
chemical formula for magnesium chloride
be?
Cl
Mg +
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Cl
Mg2+
Chapter 6: Chemical Bonds
Cl
-
Cl
26
IONIC COMPOUNDS
n 
Based on the diagram, what would the
chemical formula for magnesium chloride
be?
MgCl2
Subscript – relative
#s of atoms of the
element present.
Cl
Mg +
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Cl
Mg2+
Chapter 6: Chemical Bonds
Cl
-
Cl
27
IONIC COMPOUNDS:
CRYSTAL LATTICES
n 
chemical formula does not tell you how ions
are arranged in a compound
n 
NaCl: each ion is
surrounded by 6 oppositely
charged ions & is in a
fixed position in a rigid
framework, or lattice.
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Chapter 6: Chemical Bonds
28
IONIC COMPOUNDS:
CRYSTAL LATTICES
n 
crystals - solids whose particles are arranged
in a lattice structure
n 
shape depends on arrangement of ions in its
lattice
n 
arrangement of ions depends on
n  ratio of ions
n  relative sizes of ions
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Chapter 6: Chemical Bonds
29
IONIC COMPOUNDS: PROPERTIES
OF IONIC COMPOUNDS
n 
Properties of an ionic compound can be
explained by the strong attractions among
ions within a crystal lattice.
n 
attraction among particles in substance &
kinetic energy of particles (stronger the
attraction the more kinetic energy particles
must have before they can separate)
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Chapter 6: Chemical Bonds
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