Chemistry 1

Chapter 10
Liquids and Solids

CHM 121
General Chemistry I
Dr. Ajda Yilmaz

, Intermolecular Forces

Intramolecular vs. Intermolecular Bonding
• Intramolecular bonding: Occurs within
molecules/formula units
• Condensed states of matter: Liquids and solids
– Forces involved among particles in condensed
states
• Covalent bonding
• Ionic bonding
• Intermolecular forces: Occur between
molecules/atoms

, Intermolecular Forces



Strength of Intermolecular Forces
State Density Shape Volume (Relative to Thermal Energy / avg. KE)
Gas Low Indefinite Indefinite Weak
Liquid High Indefinite Definite Moderate
Solid High Definite Definite Strong

, Intermolecular Forces
State Changes
• Caused by the changes in the forces among the
molecules and not within the molecules
• When a molecular substance changes from solid to
liquid to gas, the molecules remain intact
 Example: When energy is added to ice, the motion of the
H2O molecules increases
• Results in greater movement and disorder characteristic of liquid water
– When more energy is added to water, gaseous state is
eventually reached
• Intermolecular distance increases, and intermolecular interaction
decreases