1. Chemical Bonding

2. Introduction to chemical bonding

3. CSCOPE Vocabulary:
valence electrons
oxidation number
ion
electronegativity
ionization energy
electron affinity
energy levels
electron orbitals
electron configuration
orbital diagrams
Lewis dot structures
covalent bond
ionic bond
metallic bond
polar
non-polar
VSEPR theory
molecular geometry

4. Chemical Bonds
Chemical Bond – a link between atoms, caused by a mutual attraction of their nuclei for electrons.
3 Types of Chemical Bonds
1) Ionic Bond (metal---nonmetal)
2) Covalent Bond (nonmetal---nonmetal)
3) Metallic Bond (metal---metal)

5. Elements and Compounds

6. Ionic Bonds
Ionic Bonds – involve a transfer of electron(s) between two atoms. One atom becomes negative(anion) and the other positive(cation). The opposite charges of the ions formed causes them to attract.
Ionic bonds usually occur between a
metal(+) and a nonmetal(-) ion.
*Ionic substances are also called salts(minerals) and have high melting pts and high boiling points because ions arrange in a repeating pattern called a crystal lattice.
*Groups of ions are called formula units.

7. IONIC BONDS

8. Covalent Bonds
Covalent bonds involve a sharing of electron pairs between two neutral atoms.
Covalent bonds are usually between two nonmetals.
Covalent compounds have low melting points and boiling points, because atoms form individual groups called molecules that are held together by weaker intermolecular forces of attraction.
*Groups of atoms held together by covalent bonds are called molecules.

9. COVALENT BONDS

10. Ionic and Covalent Bonding

11. Dogs Teaching Bonding

12. Metallic Bonds
Metallic bonds involve two or more metal atoms. The positive metal nuclei stay in a fixed position, with free-flowing electrons between them.
These “free-flowing” electrons are called delocalized electrons.
These loosely held electrons allow metals to be:
Good electrical conductors, malleable(bendable), and ductile(drawn into wires.)

13. METALLIC BONDS

15. Predict the type of bond:
C---O Mg---S
N---Na P---O
Li---F Br--Br
Rb--Cl S—Fe
S—Ba Cl--S

16. The truth about ionic and covalent bonding….
Most substances are either mostly ionic or mostly covalent, but rarely truly ionic or truly covalent!!!!!
To determine the character of a bond (or substance), one must subtract the electronegativities of each atom in a bond.

17. The Pauling Electronegativity Values

18. Electronegativity Difference
The electronegativity difference between two atoms will determine the bond character of a compound.
Electronegativity Difference
I Covalent I ionic I
0.0-Nonpolar-0.3-Polar >4.0

19. Determine the bond character between:
C---O Mg---S
N---Na P---O
Li---F Br--Br
Rb--Cl S—Fe
S—Ba Cl--S