1. TYPES OF
CHEMICAL
BONDS

2. THREE TYPES OF BONDS
Metallic bonds occur between metal atoms. This type of bond does not form compounds.
Ionic bonds result from a transfer of electrons and will occur between a highly electronegative atom (nonmetal) and an atom of low electronegativity (metal). The oppositely charged ions formed from the transfer of electrons attract.
3. Covalent bonds result from sharing of electrons and will occur between two highly electronegative atoms (nonmetals).

3. Ionic bond ·· ·· Na · + · F  Na+ ·· ·· F ·· ·· ··
An ionic bond may result from electron transfer
Atoms are held together by electrostatic attraction between positive and negative ions. ·· ·· – Na + F 
Na+ ·· ·· F ·· ·· ··

8. IONIC COMPOUNDS Ionic bonding (strong) Properties
high melting point, boiling point
mostly water soluble
solid is electrical insulator, liquid and solutions of ionic compounds are conductor
Hard & brittle
ex: NaCl

12. Covalent bond
Shared electrons are in the outer energy level of both atoms
The valence (outer) energy level of both of these H atoms now have 2 electrons.
H H ··

16. POLAR COVALENT
NONPOLAR COVALENT

17. partial positive charge partial negative charge
Polar covalent bonds +  ·· H F – ·· ··
Less electronegative
partial positive charge
More electronegative
partial negative charge

18. Covalent bond ·· ·· ·· ·· F · + · F  F ·· ·· ·· ·· F ·· ·· ·· ·· ··
Bonding electron pairs
Nonbonding electron pairs, also called lone pairs ·· ·· ·· ·· F + F  F ·· ·· ·· ·· F ·· ·· ·· ·· ·· or ·· ·· F F ·· – ·· ·· ··

19. COVALENT COMPOUNDS Mostly lower melting points than ionic compounds
Solid, liquid and aqueous solutions do not conduct electricity
Some are soluble in water and some are not
Do not break along planes

21. Trends in electronegativity
Increases because Zeff increases,
which attracts electrons more strongly.
Outermost electrons are in same energy level (same n).
Increases because
valence electrons are
closer to the nucleus
(orbitals are smaller)
so they are more
strongly attracted
to the atom.

22. Difference in Electronegativity
Electronegativity Difference
0.00
0.65
0.94
1.19
1.43
1.67
1.91
2.19
2.54
3.03
Percent Ionic Character 0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
Percent Covalent Character
100%
Difference in Electronegativity
1.67 and greater
0 to .40
.40 to 1.67
NONPOLARCOVALENT
POLAR COVALENT
IONIC

24. Multiple bonds ·· ·· F F ·· – ·· ·· ·· ·· ·· O=O ·· ·· NN ·· ··
Atoms can share more than two electrons
single bond F2
double bond O2
triple bond N2 ·· ·· F F ·· – ·· ·· ·· ·· ··
O=O ·· ··
NN ·· ··

25. Multiple bonds are fatter and stronger
N2 O2 F2
triple bond double bond single bond

26. Metallic bond
Metallic bonding can be pictured as positive metal ions in a sea of freely-moving negative electrons (delocalized electrons)
Metallic bonding is moderate to strong
Occurs between metal atoms.

28. Not blank movie

31. Metallic Solid
Infinite array of atoms held together by metallic bonding
Metallic bonding is like positive metal ions in a sea of freely-moving negative electrons
Metallic bonding is moderate to strong
Properties:
moderate-to-high melting point, boiling point
may be hard or soft
electrically conductive solid and liquid
malleable, ductile
lustrous