CH7: Kinetic Particle Model of Matter Flashcards
what is KPMM made up of?
tiny particles that are in continuous motion
what allows particles to exert forces on one another?
positive and negative charges
in KPMM, what kind of force allows for a change of state?
attractive forces
what stores of energy do particles have in KPMM?
energy in the elastic store and kinetic store
what is the total energy of a substance in KPMM?
the total energy of a substance is the sum of the total energy in the elastic potential store and the total energy in the kinetic store of all the particles of the substance. this total energy is the energy in the internal store.
what happens when a substance is heated?
when a substance is heated, the particles vibrate or move faster/vigorously and the energy in the kinetic store of particles increases. temperature of the substance rises when the average energy in the kinetic store of the particles increases.
what happens when a substance continues to be heated after its initial heating?
the particles vibrate even more vigorously and push each other further apart such that the substance expands. the forces of attraction between the particles weakens with increased separation. this increases the energy in the elastic potential store which results in more energetic particles breaking away from their positions until a change of states occur.
what is melting?
the change from solid state to liquid state when energy is transferred to the substance.
what is boiling?
the change from liquid state to gaseous state when energy is transferred to the substance.
what is freezing/solidification?
the change from liquid state to solid state when energy is transferred out of the substance.
what is condensation?
the change from gaseous state to the liquid state when energy is transferred out of the substance.
what happens to the temperature during the process of changing states?
the average energy in the kinetic store of the particles remains constant. thus, the temperature of the substance remains constant.
why do solids have fixed shapes?
particles in solid are closely packed and arranged in a regular pattern. they are held in position by strong attractive forces between them.
why do solids and liquids have fixed volume?
particles in solids and liquids have strong attractive forces between them which do not allow particles to be free of each other.
why do liquids take the shape of the container?
particles in liquids slide over each other and have strong attractive forces between them but the forces are not strong enough to hold the particles in fixed positions and in a regular pattern.
