1. I. Introduction to Bonding
Chemical Bonding
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2. A. Vocabulary Chemical Bond
attractive force between atoms or ions that binds them together as a unit
bonds form in order to…
decrease potential energy (PE)
increase stability
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3. NaCl CO2 A. Vocabulary CHEMICAL FORMULA IONIC COVALENT Formula Unit
Molecular
Formula
NaCl
CO2
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4. NaCl NaNO3 A. Vocabulary COMPOUND more than 2 elements 2 elements
Binary
Compound
Ternary
Compound
NaCl
NaNO3
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5. Na+ NO3- A. Vocabulary ION 1 atom 2 or more atoms Monatomic Ion
Polyatomic
Ion
Na+
NO3-
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6. B. Types of Bonds IONIC COVALENT
Bond Formation
e- are transferred from metal to nonmetal
e- are shared between two nonmetals
Type of Structure
crystal lattice
true molecules
Physical
State
solid
liquid or gas
Melting
Point
high
low
Solubility in
Water
yes
usually not
Electrical Conductivity
yes (solution or liquid) no
Other
Properties
odorous
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7. B. Types of Bonds METALLIC e- are delocalized among metal atoms
Bond Formation
e- are delocalized among metal atoms
Type of Structure
“electron sea”
Physical
State
solid
Melting
Point
very high
Solubility in
Water no
yes (any form)
Electrical Conductivity
Other
Properties
malleable, ductile, lustrous, alloys
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8. B. Types of Bonds Lewis Structures Ionic – show transfer of e-
Covalent – show sharing of e-
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9. Ionic Bonding - Crystal Lattice
B. Types of Bonds
Ionic Bonding - Crystal Lattice
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10. Covalent Bonding - True Molecules
B. Types of Bonds
Covalent Bonding - True Molecules
Diatomic Molecule
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11. Metallic Bonding - “Electron Sea”
B. Types of Bonds
Metallic Bonding - “Electron Sea”
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12. Metal Alloys Metal mixture Substitutional Alloys Interstitial Alloys
Atoms of original metallic solid are replaced by other metal atoms of similar size
Sterling silver, brass, pewter
Interstitial Alloys
Smalller atoms fill in the spaces (interstices) between the larger metallic atoms
Carbon steel – holes between iron atoms are filled with carbon atoms making the iron harder, stronger and less ductile
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13. C. Bond Polarity
Most bonds are a blend of ionic and covalent characteristics.
Difference in electronegativity determines bond type. EN
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14. C. Bond Polarity Electronegativity
Attraction an atom has for a shared pair of electrons.
higher e-neg atom  -
lower e-neg atom +
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15. C. Bond Polarity Electronegativity Trend (p. 151)
Increases up and to the right.
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16. C. Bond Polarity Nonpolar Covalent Bond e- are shared equally
symmetrical e- density
usually identical atoms
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17. + - C. Bond Polarity Polar Covalent Bond e- are shared unequally
asymmetrical e- density
results in partial charges (dipole) + -
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18. C. Bond Polarity Nonpolar Polar Ionic View Bonding Animations.
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View Bonding Animations.

19. C. Bond Polarity Examples: Cl2 HCl 3.0-3.0=0.0 Nonpolar 3.0-2.1=0.9
NaCl
=0.0
Nonpolar
=0.9
Polar
=2.1
Ionic
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