Heat being added or taken away from a substance may cause

a change in chemical properties
a change in state
change in the boiling point
change in the freezing point

question 2 (multiple choice worth 2 points)

“phase change” and “change of state”

are opposites
sometimes mean the same thing
are unrelated
are two terms for the same thing

question 3 (multiple choice worth 2 points)

which of the following statements about freezing points is true?

the boiling point is the same for all substances
the freezing point of a substance is higher than its boiling point
the freezing point of a substance is lower than its boiling point
the freezing point of a substance can be the same as the boiling point

question 4 (multiple choice worth 2 points)

a liquid may reach its boiling point if

heat is added to it
there are no gases in it
its solid melts easily
the temperature is low enough

question 5 (multiple choice worth 2 points)

when a liquid becomes a solid, this is called

freezing point
thermal point
boiling point
flash point

question 6 (multiple choice worth 2 points)

in condensation,

a gas becomes a liquid.
a gas becomes a solid.
a solid becomes a gas.
a liquid becomes a gas.

question 7 (essay worth 3 points)

explain how changes in temperature affect the particle motion of a substance.