States of Matter Solids, Liquids, Gases and Plasmas
States of Matter • All matter consists of particles, called atoms and molecules, that are way too small to see with the naked eye. • Atoms are the smallest part of elements • Molecules are the smallest part of compounds. • These atoms and molecules are always in motion, bumping into one another (Brownian motion). • The state of matter is determined by how fast the particles are moving and how strong the attraction between the particles is (intermolecular forces).
Solids • Molecules are close together and locked in place, but still vibrate • Definite shape and volume • Strongest intermolecular forces
Solids • Two types: • Crystalline- these solids have a very orderly 3-D arrangement of atoms. • Amorphous- are composed of atoms or particles that are arranged in no particular order.
Liquids • Molecules move fast enough to flow and slip out of position • Can change shape, but not volume • Intermolecular forces are weaker than solids, but stronger than gases
Gases • Molecules move so fast that they are widely separated • Can change BOTH shape and volume • Weakest intermolecular forces
Plasma • Atoms or Molecules are so heated they start to lose electrons, becoming ionized. • Actually the most common state of matter in the universe (due to its presence in stars), but less common on Earth.
Temperature • The higher the temperature, the higher the energy a particle has and the faster it moves. • Adding heat to a substance is also adding energy. • If you add or remove enough energy, substances tend to change states.
Changes of State • Melting - Solid to a Liquid. • Boiling / vaporization - Liquid to Gas throughout. • Evaporation - faster moving liquid particles on the surface escape to gas. • Condensation - gas to a liquid. • Freezing /Crystallization–liquid to solid • Sublimation- solid to a gas.