kinetic theory Flashcards
solids
Vibrate in a fixed position.
Keeps its shape
least energy
liquid
In contact with each other.
Can move around randomly, so has no fixed shape.
Middle Energy
gas
Move about at random much faster.
Much farther apart.
Much lower density.
Most energy
What is the role of free electrons?
> When a metal is heated, the FE in the heated part gain kinetic energy, and move faster.
> These FEs diffuse and collide with other FE and ions in the cooler parts of the metal.
> As a result, kinetic energy is transferred into these new FE’s.
How does evaporation cool a substance?
Relatively weak forces of electrostatic attraction exist between the particles of a liquid.
> The faster particles with more kinetic energy break away from the particles at the surface and escape through evaporation.
> This leaves the liquid cooler because the average kinetic energy of each particle has decreased.
The bigger the temperature difference between an object and its surroundings…
… The faster the rate at which energy is transferred.
What happens as energy spreads out?
It becomes less useful.
Conservation of energy
Energy cannot be created or destroyed.
