States of Matter Flashcards
Describe the arrangement and
movement of particles in solids
Tightly packed together in a regular
arrangement.
Vibrate in fixed positions
Describe the arrangement and movement of
particles in liquids
Close together but able to move past
each other.
Vibrate and move around each other.
Describe the arrangement and movement of
particles in gases
Well separated with no regular
arrangement.
Vibrate and move freely at high speeds.
Compare the relative energies of particles in solids,
liquids and gases
Particles in a solid have the least amount
of energy and particles in a gas have the
most energy.
What does ‘interconversion of state’ mean?
When matter changes from one state to
another due to changes in temperature
or pressure.
What are the names for the state changes from solid
to liquid and vice versa?
Solid → liquid: Melting
Liquid → solid: Freezing
What are the names for the state changes from
liquid to gas and vice versa?
Liquid → gas: Evaporation
Gas → liquid: Condensation
Describe the forces between particles in solids,
liquids and gases
Solids - Strong forces of attraction between particles which
keeps them in their fixed positions.
Liquids - Weaker attractive forces than in solids.
Gases - Weakest intermolecular forces so particles are in
random movement.
How does a physical change differ from a chemical
change?
A physical change involves changes in the forces
between particles. The particles themselves remain the
same and the chemical properties remain the same.
A chemical change is different as it affects the chemical
properties of the substance.
True or false?
‘Physical changes are relatively easy to reverse’
TRUE
Relatively easy to reverse since no new
product is formed during the changes of
state.
What is the term describing when a solid changes
straight into a gas?
Sublimation
Describe what happens, in terms of particles, when a
solid is heated and melts into a liquid
When heated the particles absorb thermal energy
which is converted into kinetic energy. The
particles in the solid vibrate more. This causes
the solid to expand until the structure breaks, and
becomes a liquid.
Describe what happens, in terms of particles, when a
liquid is heated and evaporates into a gas
When heated, the particles in a liquid expand and
some particles on the surface gain sufficient
energy to overcome the intermolecular forces
and evaporate. At the boiling point, all of the
liquid particles gain enough energy to evaporate.
Substance A melts at -183°C and boils at -50°C.
What state is A at -90°C?
Liquid
