1. Ionic and Covalent Bonding
Section 4.2

2. What holds bonded atoms together?
Atoms WANT their valence shells filled
They bond with other atoms in such a way that these valence shells get filled up

3. More about bonds Bonds can stretch and bend without breaking
There are 3 main types of bonds
Ionic Bonds
Metallic Bonds
Covalent Bonds

4. Ionic Bonds Formed between oppositely charged ions
Usually alkali metals & halogens
Sometimes alkaline earth metals and halogens
More rare combinations exist
Form as networks, not individual molecules
When melted or dissolved in water, they conduct electricity
Formed by the transfer of electrons

5. Electron Transfer – Ionic Bonds+
Fluorine
FLUORIDE -

6. Ionic compounds form networks, not molecules

7. Metallic Bonds
Form by the attraction between the nucleus of one atom and the electrons of its neighbors. - +

8. Electrons move freely between metal atoms in metallic bonds

9. Covalent Bond Facts Made of molecules, not network structures
Often formed between nonmetal atoms
Can be solids, liquids, or gases
Most compounds of this type have low melting points
Do not conduct electricity
Atoms joined by covalent bonds SHARE electrons

10. Shared Electrons in Covalent Bonds

11. Atoms may share more than one pair of electrons

12. Polyatomic Ions Some compounds have BOTH ionic and covalent bonds.
Example: Hydroxide (OH-)
Hydrogen and oxygen covalently bonded
Molecule is negatively charged, which behaves like an ion that can form an ionic bond

13. More Polyatomic Ions
Carbonate
Ammonium
Cyanide