1. Chapter 8 8.1 Molecular Compounds 8.2 The Nature of Covalent Bonding

2. Molecular Compounds Atoms will give, take or share e- to have full valence e- levels. –The compounds formed by sharing are called molecular compounds. –*No Ions are formed, no e- transferred** Molecular compounds are made up of two or more nonmetals. Ex. H2OH2O

3. Covalent Bonds The bonds formed by sharing e- Co - means together or to share Valent – means Valence e-

4. Drawing Electron Dot Structures (Lewis Dot Diagrams) for Molecular Compounds Only valence electrons are involved. A Line represents a (covalent bond) sharing of 2 e- e- one from each atom. Dots represent individual e- as before.

5. Steps for Drawing e- dot structures 1.Write the symbol for the central atom surrounded by the symbols for the outer atoms. 2.Put the dots around each atom to represent # of valence e-. 3.Draw lines from the outer atoms to the central atom connecting valence e- based on the number of bonds they need to make (shared pairs of e-). 4.Leave the valence electrons NOT used for bonding represented as unconnected dots.

6. Example H2OH2O 1. HO H 2. H - O - H 3.Notes: a. each pair of e- = = - b. H is now full 1s 2 c. O is now full 1s 2 2s 2 2p 6

7. Example CCl 4 1. Cl 2. | Cl --- C --- Cl | Cl 3.Notes: a. C is now full 1s 2 2s 2 2p 6 b. Cl is now full [Ne]3s 2 3p 6

8. Ex. CO 2 Double Bonds 1. O = C = O 2.Notes: a. C is now full 1s 2 2s 2 2p 6 b. O is now full 1s 2 2s 2 2p 6

9. Diatomic Molecules