1. I. Introduction to Bonding (p. 161 – 163)
Ch. 6 & 7 - Chemical Bonding
I. Introduction to Bonding (p. 161 – 163)

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

3. NaCl CO2 A. Vocabulary CHEMICAL FORMULA IONIC COVALENT
Metal + non metal
2 non metals
NaCl
CO2

4. NaCl NaNO3 A. Vocabulary COMPOUND more than 2 elements 2 elements
Binary
Compound
Ternary
Compound
NaCl
NaNO3

5. Na+ NO3- A. Vocabulary ION 1 atom 2 or more atoms Monatomic Ion
Polyatomic
Ion
Na+
NO3-

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

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

8. Metallic Bonding - “Electron Sea”
B. Types of Bonds
Metallic Bonding - “Electron Sea”
RETURN

9. C. Metallic Bonds
A metallic bond results from the sharing of a variable number of electrons by a variable number of metal atoms.
The electrons “float” around between the atoms, which are strongly attracted to the electrons near them. Metallic bonds are very strong.

10. C. Metallic Bonds
Because the metallic bonds are so strong, metals maintain a rigid structure, resulting in high melting and boiling points.
Metal atoms bond in a layered structure, so the layers can slide past each other, making them malleable.
Light can’t easily penetrate through these layers, and gets reflected, giving metals their lustre (shine).

11. C. Metallic Bonds
The roaming electrons are excellent charge carriers, making metals great conductors of electricity.
Because metal atoms sit so close together, they easily transfer heat to neighboring atoms, making them great heat conductors.

12. C. Bond Polarity
Most bonds are a blend of ionic and covalent characteristics.
Difference in electronegativity determines bond type.

13. C. Bond Polarity Electronegativity
Attraction an atom has for a shared pair of electrons.
higher e-neg atom  -
lower e-neg atom +

14. C. Bond Polarity Electronegativity Trend (p. 151)
Increases up and to the right.

15. C. Bond Polarity Nonpolar Covalent Bond e- are shared equally
symmetrical e- density
usually identical atoms

16. + - C. Bond Polarity Polar Covalent Bond e- are shared unequally
asymmetrical e- density
results in partial charges (dipole) + -

17. C. Bond Polarity
Nonpolar
Polar
Ionic
View Bonding Animations.

18. 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

19. C. Bond Polarity How to Calculate Percent Ionic Character:
Bigger # – Smaller # X = %Ionic
Bigger # Character