1. Forces of Attraction
Chapter 13-2

2. Intra vs. Intermolecular Forces
Intramolecular forces – means “within”
attractive forces that hold particles together in ionic, covalent, and metallic bonds;
Intermolecular forces – means “between”
Usually weaker than intramolecular forces
Accounts for attraction between particles

3. 1. Dispersion forces
Dispersion forces – weak forces that result from temporary shifts in the density of electrons in electron clouds
Weakest of the intermolecular forces; all bonds have dispersion forces
Dominant force of attraction between identical nonpolar molecules

4. 2. Dipole-Dipole forces
Dipole-dipole forces – attraction between oppositely charged regions of polar molecules
Occurs in polar molecules that have permanent dipoles

5. 3. Hydrogen bonds
Hydrogen bonds – is a dipole-dipole attraction that occurs between molecules containing a hydrogen atom bonded to a small, highly electronegative atom with at least one lone electron pair