1. The study of nuclear change.
Nuclear Chemistry
The study of nuclear change.
Some elements undergo chemical changes in their nucleus that alters their number of protons or neutrons.

2. Nucleus nucleus contains nucleons atomic mass, a.k.a. mass number
p+ and n0
atomic mass, a.k.a. mass number
protons + neutrons
atomic number
# protons
identifies the element

3. Isotopic notation
Symbol
Mass
Atomic
number
Symbol - Mass

4. U-242 U-232 U-236 U-234 U-239 U-238 U-240 U-235 U-229 U-235 U-238

5. An element is considered radioactive because it releases Energy
Transmutation
Sometimes the changes in the nucleus are such that an element is transformed into a different element
change in atomic number
An element is considered
radioactive because it releases Energy
during transmutation

6. Artificial Natural Transmutation Transmutation
Change in nucleus occurs when bombarded by an alpha particle or neutron
MUST be a reactant
Change in nucleus occurs spontaneously
The ONLY reactant is the atom undergoing transmutation

7. FYI . . . Since 1940, 23 transuranium elements have been formed
All elements with atomic numbers > 93 were synthesized by nuclear reactions
Glenn Seaborg created 10 of these elements
atomic #
Element #106 was named for him
Seaborgium

8. Stability of Nuclei Most nuclei are stable
some elements have unstable isotopes
Radioisotopes / nuclide
Ex. C-12 stable and won’t transmutate
C-14 unstable and will transmutate

9. What causes instability?
As atoms increase in size the ratio of neutrons to protons also increases
the larger the ratio the more unstable the atom
Ex. compare C-14 to U-238
All nuclei with atomic numbers > 83 are unstable and radioactive

10. Unstable nuclei stable nucleus will spontaneously decay
in order to form a
stable nucleus

11. Types of Radiation
Types of radiation emitted from the nucleus during transmutation
alpha particles He or α
beta particles ß- or
gamma radiation γ
Positrons β+ or 4 2

12. Radiation Penetration

13. How does Radiation affect cells?
Radiation has the ability to ionize atoms
Ionizing radiation causes damage to tissues by damaging molecules
Most damaging is alpha; least is gamma
Damage to proteins & DNA are most damaging
If radiation exposure is low the body may repair itself
If exposure is high, cells may die or cellular instructions might get “scrambled”

14. Radioisotopes are used in diagnosing and treating cancer
diagnose thyroid disorders
Co-60
treat cancer
Short half lives
decay quickly

15. Alpha Decay
Alpha particle has to be a product.

16. Beta Decay
A Beta particle has to be a product

17. Gamma Radiation
Type of electromagnetic radiation like an x-ray
No charge, no mass, no equations!

18. These 3 types of radiation were discovered by Rutherford

19. Positron Radiation

20. The End