Isotope not small atomic not NOT mass fraction mass bottom particular contributions add average nucleus electrons average total number add protons whole overall together NOT Name
The
mass
number
of
an
atom
is
equal
to
the
number
of
and
neutrons
found
in
the
of
a
atom
.
The
mass
number
of
a
particular
atom
is
the
same
as
the
average
of
an
element
.
The
mass
number
is
found
on
the
Periodic
Table
.
In
order
to
determine
the
mass
number
of
a
particular
atom
,
you
need
to
the
number
of
protons
and
neutrons
together
and
since
you
can't
have
a
of
a
proton
or
neutron
,
the
sum
will
always
be
a
number
.
The
number
on
the
of
each
box
on
the
Periodic
Table
is
known
as
the
atomic
mass
.
This
is
an
for
all
of
the
atoms
of
a
particular
element
.
If
you
need
to
determine
the
mass
number
of
a
particular
atom
,
do
NOT
look
on
the
Periodic
Table
for
this
number
,
since
it
is
found
there
.
Simply
the
number
of
protons
and
neutrons
in
a
particular
atom
.
The
is
a
quick
way
of
representing
the
name
or
symbol
of
the
element
followed
by
the
.
Adding
or
removing
from
the
electron
cloud
does
affect
mass
of
an
atom
since
they
are
too
to
make
a
significant
to
the
mass
of
the
atom
.