Let's review the states of matter: Solid, Liquid, and Gas.
Solids are rigid and has a fixed shape and volume.
Liquids have a definite volume; it takes the shape of its container.
Gases have no fixed volume or shape; it takes the shape and volume of its container.
Here is a fun song to help you remember the differences between the states.
Different Phase Changes
- Evaporation
- Change of phase from liquid to gas that occurs at the surface of a liquid
- The temperature of any substance is related to the average kinetic energy of its particles.
- Some particles have low kinetic energy and some have high kinetic energy.
- When there is enough kinetic energy in a particles the particle can escape in to the atmosphere
- Condensation
- The changing of a gas to a liquid
- Kinetic energy~ energy of attraction
- When gas molecules near the surface of a liquid are attracted to the liquid, they strike the surface with increase kinetic energy and become part of the liquid
- Condensation is a warming process
- Boiling
- Changes liquid to gas.
- Like evaporation
- Major difference
- Evaporation only occurs at the surface
- Boiling can occur any in the liquid.
- Freezing
- When kinetic energy is low and the energy of attraction is greater, a liquid will freeze
- Different liquids have different freezing points
- Melting
- If the kinetic energy is high enough to ~ equal to energy of attraction then the solid becomes a liquid
- Sublimation
- The process of changing from a solid to a gas without passing through an intermediate liquid phase.
- Deposition
- The process of changing from a gas to a solid without passing through an intermediate liquid phase.
Heat of Fusion and Evaporation
- Heat of Fusion
- The amount of energy/mol needed to convert between solid and liquid.
- H2O~ 6 kJ/mol
- Heat of Vaporization
- The amount of energy/mol needed to convert between a liquid and a gas.
- H2O~ 41 kJ/mol
- Heat of Fusion
Forces
- Intramolecular Forces
- Forces in a molecule
- Covalent
- Ionic
- Intermolecular Forces
- Forces between molecules
- Dipole-dipole
- hydrogen bonding
- London dispersion forces