States of Matter Investigate relationships among the pressure, temperature, and volume of gases and liquids. Distinguish among solids, liquids, gases, and plasmas Describe and illustrate the physical differences among solids, liquids, and gases in terms of their mass, volume, density, shape, and particle arrangement.

States of Matter Solids Liquids Gases

Solids Have definite shape and volume Atoms packed close together Won’t change if you change the container Atoms packed close together Ordered arrangement of atoms Almost all elements on the table are solids at room temperature

Liquids Definite volume but variable shape Atoms not as close together Takes the shape of its container Atoms not as close together More random arrangement of atoms Only mercury and bromine are liquids at room temperature

Gases No definite shape or volume Atoms far apart Takes the shape and volume of its container Atoms far apart Completely random arrangement of atoms H, He, N, O, F, Ne, Cl, Ar, Kr, Xe, Rn, are gases

Plasma 99% of all matter in the universe is in this state Ions swirling around each other at extremely high temperatures Found in stars

Kinetic Theory Molecules are always moving Molecules are always running into each other or their containers As you increase temperature, speed of molecules increases http://upload.wikimedia.org/wikipedia/commons/6/6d/ Translational_motion.gif http://www.chm.davidson.edu/vce/KineticMolecularT heory/BasicConcepts.html

Kinetic Theory and the States Gases Random, constant motion Motion of one doesn’t affect motion of another, unless they hit Attraction between atoms can be ignored Liquids Slower speed than gases Motion of one atom affects another Attraction between atoms cannot be ignored Solids Even slower speeds Atoms just vibrate in place Can’t move around or switch places

Gas Laws

Pressure Force distributed over area Larger area, less pressure SI Unit Pascal (Pa) http://abclocal.go.com/wtv g/video?id=8184575 http://www.teachertube.c om/viewVideo.php?video _id=27121&title=Death_D efying_Bed_of_Nails____ FHMS

Factors That Affect Pressure Collisions of molecules against a container cause pressure Temperature Kinetic Theory Increase temperature, speed increases Raising temperature raises pressure Volume Lowering volume raises pressure Number of particles Adding more molecules raises pressure

Charles’s Law As temperature increases, volume increases Pressure remains constant Volume is in L Temperature is in K http://mw2.concord.org/pu blic/student/gaslaws/

V1P1=V2P2 Boyle’s Law As volume decreases, pressure increases Temperature remains constant Volume in L Pressure in Pa http://mw2.concord.org/ public/student/gaslaws V1P1=V2P2

Combined Gas Law Used when multiple variables change http://mw.concord.org/m odeler1.3/mirror/chemist ry/gasexperiment.html http://www.teachertube.c om/members/viewVideo. php?title=Dry_Ice_Bomb s&video_id=55580&vpke y=

Types Phase Changes Phase changes-reversible physical change from one state to another Melting-solid to liquid Freezing-liquid to solid Vaporization-liquid to gas Condensation-gas to liquid Sublimation-solid to gas Deposition-gas to solid

Temperature and Phase Change Temperature does not change during phase change Only after all material has changed state can temperature increase or decrease

Energy and Phase Change Energy is absorbed or released during phase change Endothermic Absorbs energy Melting Boiling Subliming Exothermic Releases energy Freezing Condensing Depositing

Melting and Freezing Melting Heat of fusion Freezing Molecules become less ordered Average kinetic energy increases Temperature rises Heat of fusion Amount of energy needed to melt Freezing Molecules become more ordered Average kinetic energy decreases Temperature decreases

Vaporization and Condensation Heat of vaporization Amount of energy needed to boil Evaporation Takes place at the surface Temperatures lower than the boiling point Boiling Requires energy Kinetic energy increases Condensation Releases energy Molecules more ordered

Sublimation and Deposition Requires energy Molecules become less ordered Deposition Releases energy Molecules become more ordered