p3 changes of state and particle model Flashcards
what is the equation that links density, mass and volume
density= mass// volume
what can the particle model be used to explain?
1) density
2) states of matter
whats the process which solid turning into liquid called?
melting
whats the process that liquid turning into gas called?
evaporating or boiling
whats the process that gas turns into liquid called?
condensation
whats the process that liquid turns into solid called?
freezing
whats the process of solid turning into gas called?
sublimation
what type of change is a change in state?
physical as its the same substance you stared with, just a different form
what happens to the number of particles when a substance changes state?
the number of particles stay the same, just differently arranged. so the mass is conserved
what is specific heat capacity?
the amount of energy required to raise 1kg of a substance by 1 degrees celsius
what equation links change in thermal energy, mass, specific heat capacity and temperature change?
change in thermal energy= mass x SHC x temp change
explain latent heat
the energy needed for a substance to change state is called the latent heat.
when a change in state occurs, the energy supplied changes the energy stored (internal energy) , but not the temperature.
this is because the energy is being used to break or weaken the bonds between the particles to change state
what equation links energy for change in state, mass and specific latent heat?
energy for change in state= mass x specific latent heat
what is specific latent heat of fusion?
change of state from solid to liquid
what is the specific latent heat of vapourisation?
the change in state from liquid to solid
what is the motion of gas particles like?
at a random and constant motion
what does the temperature of the particles link to?
the kinetic energy of those particles
how does changing the temperature of a gas at a constant volume affect the pressure?
increases the pressure exerted by the gas
how does changing the temperature of a gas at a constant volume affect the pressure?
increases the pressure exerted by the gas
how can a gas be compressed or expanded?
by changing the pressure. the pressure produces a net force at right angles to the wall of the gas container
what equation links constant, pressure and mass?
constant= pressure x massh
how can work done on a gas increase its temperature?
1) if you transfer energy by applying a force, work is done.
2) doing work on a gas increases its internal energy, which can increase its temperature
methods of doing work on a gas?
MECHANICALLY- eg a bike pump, the gas applies pressure to the plunger of the pump and exerts a force on it. work has to be done against this force to push the plunger down
this transfers energy to the kinetic energy stores, increasing the temperature
