Definition of Isotopes
Table 1. Types of atomic nuclei and their frequency of occurrence
TypeZ/N
Even-even
Even-odd
Odd-even
Odd-odd
Number of
stable nuclides
160
56
50
5
3
The same relationship is demonstrated in Fig.2, which shows that
there are more stable isotopes with even than with odd proton numbers.
Radioactive isotopes can be classified into artificial and natural.
Only the latter are of interest in geology, because they are the basis for
most age-dating methods. Radioactive processes are spontaneous nuclear reactions, characterized by the radiation emitted. This may be
classified into 1) alpha radiation, 2) beta radiation, 3) gamma radiation,
and 4) electron capture.
Z = even
Z= odd
0
10
20
N
30
'" c 0
e 40
a.
- 0
:u SO
.0
E
:J
Z
60
70
80
Number of isotopes
Fig.2. Number of stable isotopes. (Radioactive isotopes with halflifes greater than
1 (j years are included)
Table 1. Types of atomic nuclei and their frequency of occurrence
TypeZ/N
Even-even
Even-odd
Odd-even
Odd-odd
Number of
stable nuclides
160
56
50
5
3
The same relationship is demonstrated in Fig.2, which shows that
there are more stable isotopes with even than with odd proton numbers.
Radioactive isotopes can be classified into artificial and natural.
Only the latter are of interest in geology, because they are the basis for
most age-dating methods. Radioactive processes are spontaneous nuclear reactions, characterized by the radiation emitted. This may be
classified into 1) alpha radiation, 2) beta radiation, 3) gamma radiation,
and 4) electron capture.
Z = even
Z= odd
0
10
20
N
30
'" c 0
e 40
a.
- 0
:u SO
.0
E
:J
Z
60
70
80
Number of isotopes
Fig.2. Number of stable isotopes. (Radioactive isotopes with halflifes greater than
1 (j years are included)