STATES OF MATTER
Melting
Melting is when a solid changes into a liquid
Requires heat energy which transforms into kinetic energy, allowing the
particles to move
Occurs at a specific temperature known as the melting point (m.p.) which
is unique to each pure solid
Boiling
Boiling is when a liquid changes into a gas
Requires heat which causes bubbles of gas to form below the surface of
a liquid, allowing for liquid particles to escape from the surface and within
the liquid
Occurs at a specific temperature known as the boiling point (b.p.) which
is unique to each pure liquid
Freezing
Freezing is when a liquid changes into a solid
This is the reverse of melting and occurs at exactly
the same temperature as melting, hence the melting point and freezing
point of a pure substance are the same. Water for example freezes and
melts at 0ºC
Requires a significant decrease in temperature (or loss of thermal energy)
and occurs at a specific temperature which is unique for each pure
substance
Evaporation
When a liquid changes into a gas. Evaporation occurs only at
the surface of liquids where high energy particles can escape from the
liquid’s surface at low temperatures, below the b.p. of the liquid
Melting
Melting is when a solid changes into a liquid
Requires heat energy which transforms into kinetic energy, allowing the
particles to move
Occurs at a specific temperature known as the melting point (m.p.) which
is unique to each pure solid
Boiling
Boiling is when a liquid changes into a gas
Requires heat which causes bubbles of gas to form below the surface of
a liquid, allowing for liquid particles to escape from the surface and within
the liquid
Occurs at a specific temperature known as the boiling point (b.p.) which
is unique to each pure liquid
Freezing
Freezing is when a liquid changes into a solid
This is the reverse of melting and occurs at exactly
the same temperature as melting, hence the melting point and freezing
point of a pure substance are the same. Water for example freezes and
melts at 0ºC
Requires a significant decrease in temperature (or loss of thermal energy)
and occurs at a specific temperature which is unique for each pure
substance
Evaporation
When a liquid changes into a gas. Evaporation occurs only at
the surface of liquids where high energy particles can escape from the
liquid’s surface at low temperatures, below the b.p. of the liquid
