Nuclear Notation
Mass number
(A = Z + N)
Atomic number
(# of protons)
N
Chemical symbol
of element
A
X
Z
= number of neutrons
Carbon isotopes
Atomic number = 6.
Carbon-12 is the common
isotope, with carbon-13 as
another stable isotope which
makes up about 1%. Carbon14 is radioactive and the basis
for carbon dating.
12C
6
13C
6
14C
6
The mass of an element that is numerically equal to the atomic mass A in
grams is called a mole and will contain Avogadro's number NA (6.0221367
x 1023/mol) of nuclei.