Chemistry: Chapter 3 States of Matter

Phases of Matter 4 phases Solid, Liquid, Gas, Plasma,

Molecules packed closely together Solid Low kinetic energy because the molecules don’t have room to move. Definite volume Definite shape

Molecules move more freely, but close together Liquids Definite volume No definite shape (Takes shape of container) Medium kinetic energy

Viscosity  Resistance of a liquid to flow. Liquids Ex. Honey, Oil

Molecules are far apart and can move freely Gas No fixed volume No definite shape (Takes shape of container) High kinetic energy (more movement = more kinetic energy)

Particles have extremely large amounts of energy. Plasma Particles have extremely large amounts of energy. Can be thought of as a gas consisting of electrons instead of atoms. Most common phase of matter in the universe. http://www.neok12.com/video/States-of-Matter/zX645353667e6d7a03795d51.htm Short video on plasma

Interactive game on states of matter http://www.brainpop.com/games/mattersorter/

Kinetic theory Kinetic theory 1. All matter is composed of small particles. (atoms, molecules, etc.) 2. Particles are in constant, random motion. 3. These particles are colliding with each other and the walls of their container.

Particles are in random, constant motion. The motion of the particles is unaffected unless they collide with one another. Forces of attraction among particles in a gas can be ignored under ordinary conditions. Kinetic Theory of Gases

Video on states of matter http://www.neok12.com/video/States-of-Matter/zX0a00427e02510841527f06.htm

The force distributed over an area. SI unit: Pascal Collisions between gas particles causes the pressure in a closed container. Pressure

Temperature – Raising the temperature will increase the pressure. Volume – Reducing the volume of a gas increases the pressure. Number of Particles – Increasing the number of particles increases pressure. Factors that affect Pressure

http://phet.colorado.edu/en/simulation/states-of-matter

Ex: basketball in the summer as opposed to one in the winter Charles’s Law The volume of a gas varies directly (same way) with the temperature of the gas. Temperature Volume Temperature Volume http://www.grc.nasa.gov/WWW/K-12/airplane/aglussac.html Ex: basketball in the summer as opposed to one in the winter

The volume of a gas varies inversely (opposite way) with the pressure of the gas. Boyle’s Law Pressure Volume Pressure Volume http://www.grc.nasa.gov/WWW/K-12/airplane/aboyle.html

http://www.grc.nasa.gov/WWW/K-12/airplane/aglussac.html http://www.grc.nasa.gov/WWW/K-12/airplane/aboyle.html

V1 = V2 T1 T2 P1V1 = P2V2 T1 T2 Charles’s Law Boyle’s Law Combined Gas Law

Practice Problems Gas Laws 1. At a temperature of 280K, the gas in a cylinder has a volume of 20.0L. If the volume of the gas is decreased to 10.0L, what must the temperature be for the gas pressure to remain constant? What do we know? Which formula do we use? What are we solving for?

2. If the volume of a cylinder is reduced from 8. 0L to 4 2. If the volume of a cylinder is reduced from 8.0L to 4.0L, the pressure of the gas in the cylinder will change from 70kpa to? What do we know? What formula do we use? What are we solving for?

3. If a gas has a volume of 1L at a pressure of 270kpa, what volume will it have when the pressure is increased to 540Kpa? Assume the temperature and number of particles are constant. What do we know? What formula do we use? What are we solving for?

Gas law help GREAT website http://www.chemteam.info/GasLaw/KMT-Gas-Laws.html

Open the science of diving Interactive powerpoint

Phase Changes Changing from one phase to another by decreasing or increasing kinetic energy. Kinetic Energy *Reversible Physical Change

The temperature is one way to recognize a phase change. The temperature will not change during the change, it will change once the transformation is complete! Temperature and Phase Change

According the this chart, which phase of matter has the most heat energy? gas

Solid – Liquid – Gas – Plasma Energy is absorbed or released. Endothermic – absorbed Exothermic - released Energy and Phase Change Energy Increases Solid – Liquid – Gas – Plasma Energy Decreases

Melting Solid  Liquid Heat of fusion – amount of energy absorbed for water Freezing Liquid  Solid

Gas  Liquid Ex. clouds Liquid  Gas Condensation Vaporization Energy must be absorbed – heat of vaporization Evaporation  on the surface of a liquid at temperatures below the substances boiling point (100°C for water)

Solid  Gas (without changing to a liquid) Sublimation Solid  Gas (without changing to a liquid) Ex. Dry ice

Gas  Solid (reverse of sublimation) Deposition Gas  Solid (reverse of sublimation) Ex. Frost on windows