1. Ch. 25.5 Applications and Effects of Nuclear Reactions
CHM Hon.

2. Last class…we talked about nuclear fission:

3. Today…
We will discuss another application of nuclear chemistry: MEDICINE

4. Detecting Radioactivity
Ionizing radiation = radiation energetic enough to ionize matter with which it collides
Geiger Counter makes use of ionizing radiation

5. Detecting Radioactivity
Geiger counter: radiation detection device

6. Detecting Radioactivity
Scintillation counter
Uses phosphor-coated surface to detect radiation
Scintillations = bright flashes of light produced when ionizing radiation excites the electrons in certain types of atoms (phosphors)
The number and brightness is detected / recorded, determines the amount of ionizing radiation present

7. Uses of radiation Neutron activation analysis
Detects trace amounts of elements in a sample
Used in computer chip technology (analysis of composition)
Bombardment with stream of neutrons
Type of radiation emitted determines the types / quantities of elements present

8. Uses of Radiation
Used to follow the course of an element through a chemical reaction
Helps Scientists understand processes
Radiotracer = radioisotope that emits non-ionizing radiation and is used to signal the presence of an element or specific substance.
Iodine-131

9. Uses of Radiation
Positron emission transaxial tomograpgy (PET)

10. Uses of Radiation Radiation therapy
Used to treat cancer by destroying unhealthy cells, fast-growing cells
Down side: also kills good cells!

11. Biological Effects of Radiation
Can be very harmful
Damaged produced depends on:
energy of radiation
type of tissue
Distance
Gamma rays easily penetrate human skin

12. Biological Effects of Radiation
Ionizing radiation damage to living systems
SOMATIC: affects non-reproductive body tissue
GENETIC: damages reproductive tissue

13. Biological Effects of Radiation
Dose – the amount of radiation your body absorbs from a radioactive source
Rad (Radiation absorbed dose)
Rem (roentgen equivalent for man)