1. Nuclear Chemistry

2. Regular chemical Reactions
electrons do all the work
atom identity is unchanged
energy is involved
Nuclear Reactions
Nucleus (protons and neutrons are involved)
atom identity changes!!
HUGE energy is involved

3. Proton +1
amu

4. Electron -1
amu

5. Neutron
0 charge
amu

6. Proton Electron Neutron -1 +1 0 charge 1.000000 amu 0.001837 amu

7. In the following illustrations:
N = a neutron
P = a proton

8. N P

9. N N P N P N P N P N P N N P P N

10. C Sn Pb Si Ge (These are all Group 14 elements)
Protons Neutrons
Protons Neutrons N P 12 C
119 Sn 6 50 N P N P P N P N N P P N P N P N N
207 N P Pb 28 Si N P P P N N P N P 82 14
(These are all Group 14 elements) 73 Ge 32
(Note: small nuclei are often stable when they have the same number of protons and neutrons. As the nuclei get bigger, they need a larger proportion of neutrons. Above 82 protons, lead, all nuclei are unstable, and are thus radioactive.)

11. U (An unstable atom can emit an alpha particle to become more stable)
Protons Neutrons
238 92
(An unstable atom can emit an alpha particle to become more stable)

12. U (an alpha particle, aka a helium nucleus)
Protons Neutrons
Protons Neutrons
238 U N N N P P P 92 P N N N N N N N P N N P P N P N P P N N N N P P N N N P P P N P N N N N N P P P N P N N N N P P N P P P N N P P P N P N N N N N N P N N N P N N P P N N N P P P N P P N N N N P N P N N N N N N N N N P N P P P N N P P P N N P N N P N N N N N N N N P N P N N P N P N N P P N P N N
(an alpha particle, aka a helium nucleus) N P P N N P N N N N N N P N N P N P P N P P N N N P N N P P N P N N N P N N N N N P P P N N N P N N P P P N P N N P N P N P N P N N N P N N P N P N P P N N N N P N N P
234
(Losing 2 protons and 2 neutrons results in a change to a Thorium atom, Th) 90

13. Protons Neutrons U 92
238 N N N P P P N N P N N N N N P N N N P P N P P N P P N N N P P N P N P P N N N N N P P P P N N N N N N N N P P P N N P N P P N P N N N N P N P P P N N N N P N N N P P N N P P P N P P N N N N P N N N P N N N N N N N P N P N P P P P N N P N N P N N N P N N N N N N N N P N N P N P N N P P N P N P N P N N N N P N P P N P N N N N N N N N N P N P N P P P N N N P P N N P N P P N N P N N N N N N P P P N N N P N P N P P P N N N P N N N N P N P N N N P P P N P N P P N N N N P N N P
(Or an unstable uranium atom can convert a neutron into a proton by spitting out an electron, a beta particle)

14. Protons Neutrons U 92
238 N N e N P P P N P N N P N N N P N N P P P N P N P N N N N P P N P N N N P P P N N N P P P P N N N N N N N N P P P N P P P N P N N N P N N N P P N P N N N N P P N P N P P N P N N N N P P N N
(Note: this high energy electron, the beta particle, comes from the nucleus, not the electron cloud) P N N N N N N P N N N N N N P N P P N N P P P P N N P N N N P N N N N N N N N P P N N N P N P N P N N P N P N P N N N P P P N N P N N N N N N N N P N N P N N P P N P P N P N P N P N P N N P N N N N P P P N N N N P P P N N P N P N N N P N P N P N N N P N N N P P N P P N P N N N N P N N P
238
(Since the atom now has one more proton, it is now neptunium, Np) 93

15. Gamma radiation.
Gamma radiation is merely energy (an electromagnetic wave) that is given, often accompanying alpha or beta radiation. It is not a particle at all.

18. NUCLEAR CHEMISTRY - Radioactivity & Radiation - Alpha, Beta, Gamma.mp4

22. Radiation Notes Types of Radiation Ionizing radiation
have high energy and "ionize" the atoms they hit
alpha, beta, gamma
Non-ionizing radiation
low energy
TV, radio, microwave, light, etc.

23. Ionizing Radiation Sources
Radiation Notes
Ionizing Radiation Sources
the earth, dirt and rocks
bricks and concrete
space
Xrays
smoke detectors

24. Radiation Notes Radiation and Health Adverse Effects
overexposure leads to radiation sickness and death (hours to weeks). Body functions stop
lesser amounts affect living cells and MAY result in cancers and chromosomal mutations, which may lead to birth defects
"Background radiation" (the normal radiation exposure from space and the environment)
damages cells but our bodies can normally repair
Individual tolerances vary a

25. Radiation Notes Radiation and Health Beneficial Effects
Radioactive TRACERS can be used to detect diseases, abnormalities and cancers
Controlled radiation can stop and kill some cancers. BUT the radiation also kills normal cells. Strategies:
Carefully target only cancer areas
Because cancers often can't repair themselves as well as normal cells, use doses that kill the cancer cells but don't overwhelm normal cells.

27. Radioactivity test today! Omit:
Version A: 8, 9, 18, 19
Version B: 1, 2, 3, 4

28. Nuclear Chemistry
Radioactivity: small pieces (eg alpha, beta) are emitted
Fission: a large atom splits!
Fusion: two small atoms (like H) combine (fuse) to from a larger (He).

29. Nuclear Fission
When hit by a neutron, an unstable nucleus SPLITS, forming two smaller nuclei and releasing more neutrons. These neutrons hit more unstable nuclei resulting in a CHAIN REACTION.
This is the type of nuclear reaction that is used in all nuclear power plants.

30. Nuclear Fission U Kr + + Ba (and a heck of a lot of energy!!) N P N N
Protons Neutrons P N Kr N + + N N N P N Ba
(and a heck of a lot of energy!!)

31. Smaller nuclei FUSE to form a larger nucleus. H + H He
Nuclear Fusion
Smaller nuclei FUSE to form a larger nucleus. H + H He
Takes place on the sun and is the source of the sun's energy and thus of all life on earth!!!

32. Nuclear Fusion H + H He (and a heck of a lot of energy!!) P N N P N P

33. Comparing Fission and coal for producing energy

34. Comparing Fission and coal for producing energy
Advantages of Fission:
environmental and health impacts of nuclear power plants are minimal compared with coal-fired power plants
fission reactions produce no air pollution or the greenhouse gas CO2
a 1000 megawatt nuclear reactor uses 25 tons of fuel a year (and 25 tons of radioactive waste). A comparable coal-fired plant uses 2.5 million tons of fuel per year and produces millions of tons of CO2, SO2, and nitrogen oxide compounds (which contribute to acid rain)

35. Comparing Fission and coal for producing energy
Disadvantages of Fission:
nuclear plants are exceedingly EXPENSIVE to build
radioactive waste is generated that may cause long-term health problems, lasts virtually forever, and requires disposal that is difficult and controversial
although the potential for a nuclear accident is small (compared with coal plants), such an accident could cause catastrophic loss of life and property.

36. Comparing Fission and Fusion for producing energy
Fusion reactions produces 20 times the energy of fission for the same mass of fuel.
Fusion fuel, hydrogen, is very abundant and safe, unlike the uranium or plutonium used for fission
Fusion reactions do not produce radioactive products or air pollution
Fusion reactions are easier to control, reducing the risks of fires and explosions
BUT because it takes milliions of degrees to start a fusion reactor, we have, thus far, been able to get more energy out than is needed to start the reaction. Intensive research is underway.

37. Final Exam Answers re Fission and Fusion
135.
Nuclear fission is the process by which a single large nucleus breaks apart into two smaller nuclei. Three different products form in any nuclear fission reaction are smaller nuclei, neutrons, and energy.
Two major concerns people have about nuclear reactions are the possibility of nuclear accidents and the issue of how to dispose of nuclear waste.
Nuclear fusion is the reaction that occurs when two small nuclei join together to form a larger nucleus. The sun's energy is produced when hydrogen nuclei fuse to make helium nuclei.
Although fusion is cleaner, safer, and more efficient than fission for producing energy, it is not currently used to produce energy because of the large amount of heat required to start the reaction.

38. Whew! I'm done teaching chemistry for the year!
(Your heads must be really full)

39. What to do now...
Work on final review packet
Work on cheat sheets

42. Attachments
NUCLEAR CHEMISTRY - Radioactivity & Radiation - Alpha, Beta, Gamma.mp4