CH. 3 States of Matter

1. CH. 3 States of Matter

2. I. Solids, Liquids, and Gases • Describing the states of matter – materials can be classified as solids, liquids, or gases based on whether their shapes and volumes are definite or variable 1. solid = the state of matter in which materials have a definite shape and a definite volume 2. liquid = the state of matter in which material has definite volume but not a definite shape

3. gas = the state of matter in which a material has neither a definite shape or definite volume • plasma = state of matter which displays characteristics of a gas and liquid-high temp (lightning/stars)

5. B. Kinetic theory – states that matter says that all particles of matter are in constant motion C. Explaining the behavior of gases 1. motion in gases a. there are forces of attraction among the particles in all matter 2. kinetic theory of gases a. the constant motion of particles in a gas allows a gas to fill a container of any shape or size

6. D. Explaining the behavior of liquids 1. a liquid takes the shape of its container because particles in a liquid can flow to new locations 2. the volume of a liquid is constant because forces of attraction keep the particles close together

7. E. Explaining the behavior of solids 1. solids have a definite volume and shape because particles in a solid vibrate around fixed locations

8. Slower air = more pressure Direction of spin Wing of an airplane: http://ksnn.larc.nasa.gov/pokemon/unseen/main.html Curve ball Curve Ball in motion: http://www.grc.nasa.gov/WWW/K-12/airplane/foil2b.html Air resistance Faster air = less pressure Thrown this direction

9. II. The Gas Laws • Pressure – the result of a force distributed over an area 1. collisions between particles of a gas and the walls of the container cause the pressure in a closed container of gas B. Factors that affect gas pressure – its temp, its volume, and the number of its particles 1. raising the temperature of a gas will increase its pressure if the volume of the gas and the number of particles are constant

10. 2. reducing the volume of a gas increases its pressure if the temperature of the gas and the number of particles are constant 3. increasing the number of particles will increase the pressure of a gas if the temperature and the volume are constant

11. C. Charles Law 1. Charles’s law states that the volume of a gas is in direct proportional to its temperature in Kelvin if the pressure and the number of particles of the gas are constant a. The mathematical expression is: V1 = V2 T1 T2

14. D. Boyle’s Law 1. Boyle’s law states that the volume of a gas is inversely proportional to its pressure if the temperature and the number of particles are constant a. The mathematical expression is: P1V1 = P2V2

15. E. Combined gas law 1. The combined gas laws of Boyle’s and Charles’ can be explained by a single law that describes the relationship among the temperature, volume, and pressure of a gas when the number of particles is constant a. Mathematical expression: P1 V1 = P2 V2 T1 T2

16. III. Phase changes A. Characteristics of phase changes 1. the temperature of a substance does not change during a phase change B. Melting and freezing 1. the arrangement of molecules in water becomes less orderly as water melts and more orderly as water freezes

17. C. Vaporization and condensation 1. evaporation takes place at the surface of a liquid and occurs at temperatures below the boiling point • Sublimation and deposition 1. sublimation is the phase change in which a substance changes from a solid to a gas or vapor without changing to a liquid first

18. Sublimation Condensation Deposition Evaporation Melting Freezing