When
a
gas
is
heated
the
average
____________________
energy
of
the
particles
increases
resulting
in
an
increased
____________________
so
the
particles
hit
the
sides
harder
and
more
often
resulting
in
higher
____________________
.
If
the
____________________
on
the
outside
is
kept
constant
the
piston
will
move
____________________
increasing
the
____________________
.
This
reduces
the
____________________
of
the
particles
so
they
don't
hit
the
walls
so
often
.
The
____________________
,
therefore
,
falls
until
it
is
the
same
as
before
.
This
describes
____________________
Law
.