Topic 4: Matter, Phases and Gas laws

• Substances in a mixture may be seperated by their size, polarity, density, boiling point, and freezing point

• Filtration and distillation are examples of processes used to seperate mixtures

Three Phases

• Solids have a constant volume and shape. Particles are held in a ridgid, crystalline structure

• Liquids have a constant volume but a changing shape. Particles are mobile but still held together by a strong attraction

• Gasses have no set volume or shape. They will completely fill any closed container. Particles have largely broken free of the forces holding them together

Gas Laws

• Increasing pressure causes a decrease in volume

• Increasing tempature causes an increase in volume

• Increasing tempature causes an increase in pressure

Heating Curves

• When the substance undergoes a phase change, there is no change in tempature. The line flattens until the phase change is complete

• when a phase change is occuring, the potential energy of the substance changes wile kinetic energy remains the same

• as tempature increases kinetic energy increases

When energy is absorbed

• Melting/Fusion: Solid → Liquid

• Boiling/Evaporation/Vaporization: Liquid → Gas

• Sublimation: Solid → Gas

When energy is released

• Freezing/Solidification/Crystalization: Liquid → Solid

• Condensation: Gas → Liquid

• Deposition: Gas → Solid

The Kinetic Molecular Theory

• Are in random motion

• Have no forces of attraction between them

• Have a negligible volume compared to the distances between them

• Have collisions that result in the transfer of energy from one particle to another, but there is no net loss of energy from the collision