1. Our Radioactive World
Do you know some of the uses of radiation?

2. Much of the radiation in our world is naturally ocurring and useful
Much of the radiation in our world is naturally ocurring and useful. This is the electromagnetic spectrum. Note that it includes gamma rays which we will encounter in our study of nuclear chemistry.

3. RADIATION Non-Ionizing Ionizing Visible Light Microwaves Infrared
TV – Radio Waves
Radar Waves
High Energy UV
Radioactive Atoms
Gamma Rays
Neutrons
X-Rays
Some radiation has enough energy to knock electrons from atoms. This is called ionizing radiation. The ions created may cause damage to human tissue. The ions created are reactive and want to bond with something.

4. We will also look at particles that can be emitted during nuclear reactions. Do not worry about the spherical versus deformed nucleus distinction.

5. General Terms
Note that Parent and daughter are general names used to describe the species involved in nuclear reactions.

6. Alpha Radiation Alpha Radiation Large nuclei may be unstable.
Spit out an alpha particle.
Note the symbol for alpha.

7. Parent
This just shows the nucleus of a plutonium atom. For nuclear reactions, we are not concerned with the valence electrons, like with chemical reactions.

8. Daughter
When Pu undergoes alpha decay, U-235 is the daughter nuclide produced along with the alpha particle that got ejected from Pu’s nucleus.

9. Alpha Decay Equation
You will be expected to be able to write these equations which keep track of the species involved. Note that atomic numbers on the right add up to the atomic number on the left as do the mass numbers.

10. Beta Radiation A neutron is converted into a proton and an electron.
Electron is ejected.
Note the symbol for a beta particle. Notice that it is simply an electron. The lower right –hand diagram shows that in the nucleus a neutron splits into a proton and an electron during beta decay.

11. Parent
Note the mass number and atomic number are properly represented here.

12. Daughter
Beta decay of carbon-14 produces nitrogen-14.

13. Beat Decay Equation
Note that the beta particle has a negative charge.

14. Gamma Decay Nucleus is more stable.
The release of energy brings the nucleus to a lower energy and thus is more stable. Cobalt-60 is used to irradiate food. The high energy released kills bacteria on the surface of food.

15. 232U 232U +γ Gamma Decay Equation
Note that there is no change in mass number, nor atomic number.

16. Try to fill this out before revealing the answers.

21. Penetration Ability
I can’t read Japanese, but the picture is great.

23. Penetrating Ability
Simpler picture but not as cool as the Japanese one.

25. Alpha Particle a Characteristics • +2 charge • 2 protons • 2 neutrons
• Large mass
Range
• Very short
range
• 1" -2" in air
Shielding
• Paper
• Outer layer
of skin
Hazards
• Internal
Sources
• Plutonium
• Uranium
• Radium
• Thorium
• Americium a a a a a

26. Beta Particle b Characteristics • -1 charge • Small mass Range
• Short range
• About 10'
in air
Shielding
• Plastic
safety
glasses
• Thin
metal
Hazards
• Skin and
eyes
• Can be
internal
Sources
• Radioisotopes
• Activation
Products
• Sealed
sources

27. Gamma Ray g Characteristics • No charge • No mass • Similar to x-rays
Range
• Long range
• About 1100'
in air
Shielding
• Lead
• Steel
• Concrete
Hazards
• External
(whole body)
• Can be
internal
Sources
• X-ray
machines
• Electron
microscopes
• Sealed
sources
• Accelerators
• Nuclear
reactors
• Radioisotopes
Paper
Plastic
Lead