The 3 States of Matter

Kinetic Theory : Concepts for “States” of Matter All atoms and molecules are always in Motion Molecules in solids, liquids and gases vibrate differently

Solids Particle Arrangement: tightly fixed in one position Definite Shape Definite Volume Two Types: Crystalline - Crystal Shaped Amorphous - No Regular Pattern

Liquids “Fluid” means to flow freely Particle Arrangement: “somewhat” fixed, but move more freely No Definite Shape, take shape of container Definite Volume Unique Property: Viscosity- A liquids resistance to flow Ex. Syrup is highly viscous

Gases Particle Arrangement: movement is entirely Free No Definite Shape No Definite Volume * Gases particles fill all of the space available, thus have the same volume as the container they fill

Gases Gas Particles constantly collide with one another and are always “pushing” on the sides of the container in which they fill Pressure is the force of the outward “Push” divided by the area of the container P = Force Area

Images of the 3 States of Matter Particle Arrangement

A change from one state of matter to another (solid → liquid → gas) Only the movement of molecules changes The number of molecules stays the same The mass remains the same Phase changes are physical changes (reversible)

Temperature: a measure of the average energy, the random motion, of particles in matter Kinetic Theory: Concepts for Phase Change Heat is Energy Higher Temps = more energy = Increased Speed Lower Temps = less energy = Decreased Speed

Melting Phase change from a solid to a liquid Molecules speed up, move farther apart, and absorb heat energy

Melting, Freezing, Condensation, Evaporation Sublimation (solid to gas) below 0 °C is called a solid. between 0 and 100 °C water is a gas at temperatures above 100°C

Freezing Phase Change from a liquid to a solid Molecule slow down, move closer together and release heat energy.

Vaporization (Boiling) Phase change from a liquid to gas. It occurs at the boiling point of matter. Molecules speed up, move farther apart, and absorb heat energy.

Evaporation Phase change from a liquid to a gas on the surface of a liquid (occurs at all temperatures). Molecules speed up, move farther apart, and absorb heat energy.

Condensation Phase change from a gas to a liquid. Molecule slow down, move closer together and release heat energy.

Sublimation Phase change from a solid to a gas. Molecules speed up, move farther apart, and absorb heat energy.

Melting Point: The temperature at which a solid changes into a liquid. Boiling Point: The temperature at which a liquid changes into a gas.