Thermal Physics Definitions Flashcards
Gases
Widely spaced particles with weak forces.
Liquids
Particles in contact but able to flow.
Solids
Tightly packed particles vibrating in place.
Brownian motion
Random motion of suspended particles.
Gas temperature
∝ average kinetic energy of molecules.
Kinetic molecular model
Matter composed of moving particles.
Pressure of a gas
Momentum transfer per area by particle collisions.
Suspension
Particles dispersed in a fluid.
Evaporation
Molecules escape liquid surface to vapor.
Evaporative cooling
Cooling from escape of high-energy molecules.
Kelvin
Absolute temperature scale; 0 K = Lowest possible kinetic energy kinetic energy.
Molecule
Two or more atoms chemically bonded.
Temperature
∝ average kinetic energy.
Absolute zero
Least possible temperature where particles have lowest possible kinetic energy (0�K OR -273�C
Volume of a gas
Three-dimensional space occupied.
Thermal expansion
Size change with temperature.
Specific heat capacity
Energy to raise 1 kg by 1 °C.
Thermal capacity
Energy for unit temperature change.
Latent heat
Energy for state change at constant temperature.
Melting
Solid to liquid transition at melting point.
Melting point
Solid–liquid transition temperature.
Boiling
Liquid to gas transition at boiling point without temperature change.
Boiling point
Temperature of liquid–gas state change.
Condensation
Vapor to liquid on cooling.
