PARTICLE MODEL OF MATTER Flashcards
DENSITY (KG/M3)= INCLUDE UNITS
MASS(KG) /VOLUME (M3)
A dense material has its particles…
packed tightly together
a less dense material has its particles…..
spread out
what happens when you compress a material
the particles of the material would move closer together making it more dense
SOLIDS ARE
strong forces of attraction hold the particles close together in a fixed regular arrangement. The particles don’t have much energy so the particles vibrate in fixed positions. The density is the highest because the particles are close together
LIQUIDS
there are weaker forces of attraction between the particles. The particles are close together but can move past each other and form irregular arrangements they have more energy than the particles in a solid and they move in random directions at low speeds
GASES
there are almost no forces of attraction between the particles. The particles have more energy than in liquids and solids theyre free to move and travel in random directions at high speeds. Gases are less dense.
what is internal energy
internal energy is the total energy that its particles have in their kinetic and potential energy stores
where is energy stored in a system
in its particles
what happens when you heat a system
heating a system transfers energy to its particles in which they gain energy in their kinetic stores and move faster therefore increasing its internal energy. This leads to a change in temperature or state because there is enough energy in its kinetic energy store to break the bonds holding it together
is mass lost when their is a change of state
NO there isn’t mass is conserved
Explain how heating a solid causes a change in state
Heating the solid transfers energy to the kinetic energy stores of the particles. when the particles have enough energy in their kinetic energy stores they can break the bonds holding them together making the solid change state to a liquid
what is sublimation
solid to gas in one step
what is specific latent heat
is the amount of energy needed to change 1kg of the substance from one state to another
either solid and a liquid (fusion)
or liquid and a gas (vaporisation)
what is the specific latent heat for changing between a solid and a liquid
specific latent heat of fusion
what is the specific latent heat for changing between a liquid and a gas
specific latent heat of vaporisation
FORMULA FOR SPECIFIC LATENT HEAT
ENERGY= MASS X SPECIFIC LATENT HEAT
Pressure and volume are…
inversely proportional
if pressure increases
volume decreases
if volume increases
pressure decreases
what happens when particles move about at high speeds
they collide with each other and create pressure when they collide against the walls of a container
In a sealed container what is the outward gas pressure
it is the total force exerted by all of the particles in the gas on a unit area of the container walls
faster particles and more frequent collisions lead to…
an increase in gas pressure
(IF THE VOLUME IS CONSTANT) increasing the temperature inside something
will increase speed of the particles therefore increasing the pressure
(IF THE TEMPERATURE IS CONSTANT) increasing the volume of a gas inside something means
the particles get more spread out and hit the walls less often therefore meaning the gas pressure decreases
Doing work on a gas increases
the gases internal energy
Explain, in terms of particles, how evaporation causes the cooling of water.
the fastest particles have enough energy
to escape from the surface of the water
therefore the mean energy of the remaining particles decreases
the lower the mean energy of particles the lower the temperature (of the water)
