topic 3 Flashcards
a change of state requires
energy
when a substance is melting or boiling, what increases
the internal energy, but the energy is used for breaking intermolecular bonds rather than raising the temperature
when a substance is freezing or condensing, what is formed
bonds are formed between particles, which releases energy
what is latent heat
the amount of energy needed to to change 1kg of it from one state to another without changing temperature
for cooling, what is latent heat
the energy released by a change in state
what is the specific latent heat called when changing between a solid and a liquid
specific latent heat of FUSION
what is the specific latent heat called when changing between a liquid and a gas
specific latent heat of VAPORISATION
a solid all the way to a gas is called
sublimating
liquid to a solid is called
freezing
solid to a liquid is called
melting
liquid to a gas is called
boiling
gas to a liquid is called
condensing
describe solids (3)
- strong forces of attraction hold particles together
- in a fixed, regular arrangement
- particles don’t have much energy so only VIBRATE about their fixed positions
describe liquids (4)
- there are weaker forces of attraction between particles
- particles are close together, but can move past each other and form irregular arrangements
- have more energy than particles in a solid
- move in random directions at low speeds
describe gases (3)
- there are almost no forces of attraction between particles
- particles have more energy than in liquids or solids- they’re free to move
- constantly moving in random directions at speeds
when gas particles collide with something what happens
they exert a force on it
what is pressure
the force exerted per unit area
colliding gas particles creates ….
pressure
if you increase the temperature of a gas, what happens
you transfer energy into the kinetic energy stores of its particles
so increasing the temp of a gas, what else increases
the average speed of its particles
what does the density of an object depend on
what its made of and how the particles are arranged
in a dense material how are the particles arranged
the particles are packed tightly together
in a less dense material how are particles arranged
the particles are more spread out
in a less dense material, compressing the particles has what effect on the particles
the particles would move closer together and it would become more dense
in terms of density, solids are more dense than…
liquids
in terms of density, gases are less dense than…
liquids
what is density
the measure of the compactness of a substance-it relates to the mass of a substance and how much space it takes up
what type of change is a change of state called
physical
what is a physical change
when you end up with the same substance but in a different form
in a change of state what happens to the mass
it is conserved
