1. Hank Miller & Haley Vollmer
Alpha, Beta, & Gamma Rays
Hank Miller & Haley Vollmer

2. What is an atom? Are made up of protons, electrons, and neutrons
Protons and neutrons make up the nucleus with the electrons on the outside
In some types of atom, the nucleus is unstable, and will decay into a more stable atom. This radioactive decay results in Alpha, Beta, or Gamma Rays.

4. Alpha Particles
Alpha- these are fast moving helium atoms. They have high energy, but due to their large mass, they are stopped by just a few inches of air.

5. Characteristics of Alpha Particles
Made of 2 protons and 2 neutrons
+2 charge
Mass=4
High ionization- meaning it strips molecules of its electrons
low penetrating power - you can stop them with just a sheet of paper.

6. Beta Particles
Beta- these are fast moving electrons. Since electrons are much lighter than helium atoms, they are able to penetrate further, through several feet of air, or several millimeters of plastic or less of very light metals.

7. Characteristics of Beta
Charge of -1
Mass= 1/2000th of a proton. This means that beta particles are the same as an electron.
medium penetrating power - they
are stopped by a sheet of aluminum.

8. Gamma Rays
Gamma- these are photons, just like light, except of much higher energy. X-Rays and gamma rays are really the same thing, the difference is how they were produced.
Depending on their energy, they can be stopped by a thin piece of aluminum foil, or they can penetrate several inches of lead.

9. Characteristics of Gamma
Gamma rays are waves, not particles.
This means that they have no mass and no charge.
High penetrating power - it takes a
thick sheet of metal such as lead,
or concrete to reduce them significantly.

10. Characteristics of Gamma (cont.)
Gamma rays do not directly ionise other atoms, although they may cause atoms to emit other particles which will then cause ionisation.

11. Gamma Rays Can be characterized by frequency, wavelength, and energy.
Has the highest frequency on the electromagnetic spectrum
electromagnetic spectrum= includes the entire range of wave lengths or frequencies of electromagnetic radiation.

12. Penetration
Alpha
Beta
Gamma

13. Radioactive Decay
Alpha, Beta, and Gamma rays originate from the radioactive decay of certain elements.
Radioactive decay occurs from elements with an unstable nucleus.
Certain numbers of protons and neutrons can make a stable nucleus.

14. Radioactive Decay (cont.)
Elements without the same number of protons and neutrons tend to be unstable.
An unstable nucleus will decay into a stable nucleus.
This decay is the source of Alpha, Beta, and Gamma rays.

15. Nucleus Stability
When we plot a graph of "Number of neutrons" against "Number of protons", we find that stable elements lie on a "stability line".
Elements which are not on this line are unstable, and we find that they tend to undergo alpha-decay or beta-decay and get closer to the stability line.

16. Stability Line

17. Alpha Decay
When an element undergoes an Alpha decay, its atomic number decreases by 4
This is due to the loss of the Alpha particle
Remember that an Alpha particle has a mass of 4 (2 protons, 2 neutrons)
The Alpha decay of Americium 241 to Neptunium 237

18. Basic Beta Decay
Occurs when neutron to proton ratio is too GREAT in the nucleus
A neutron is turned into a proton and an electron
The electron is emitted

19. Positron Emission Beta Decay
Occurs when the neutron to proton ratio in the nucleus is too SMALL
A proton will turn into a neutron and a positron=positively charged electron
Positron is emitted

20. Electron Capture Beta Decay
Occurs when neutron to proton ratio in the nucleus is too SMALL
The nucleus will capture an electron which basically turns a proton into a neutron
Electron capture with beryllium-7

21. Gamma Decay Occurs when nucleus has too much energy
Nucleus will emit a high energy photon, a.k.a. a gamma particle, to fall down to a lower energy state

22. Quiz Question #1 When is a nucleus unstable and most likely to decay?
A. Same number of protons as neutrons
B. More protons than neutrons in the nucleus
C. More neutrons than protons in the nucleus
D. Both B and C

23. Quiz Question #2 What is emitted due to gamma decay?
A. A high energy photon
B. Electron(s)
C. Helium Ions
D. Alpha particles

24. Quiz Question #3 What material can stop a beta particle?
A. A piece of paper
B. Thin sheet of aluminum
C. Thin layer of clothing
D. Nothing can stop it

25. Quiz
Question #4
When an element undergoes Alpha Decay, how much does its atomic number decrease by?
A. 4
B. 6
C. 8

26. A. The highest frequency
Quiz
Question #5
Gamma Rays have what kind of frequency on the electromagnetic spectrum?
A. The highest frequency
B. The lowest frequency
C. Average frequency
D. No frequency

27. Works Cited http://home.clara.net/darvill/nucrad/types.htm

28. Congratulations!!!
You have just finished the quiz and you are now done with the tutorial.
Click here to end show

29. You dropped the ball!!! Go back and try again.

30. Correct! Click for next question.

31. Correct! Click for next question.

32. Correct! Click for next question.

33. Correct! Click for next question.

34. Correct! Click for next question.