1. Nuclear Reactions

2. Nuclear Decay Song on Youtube
Animation of Alpha, Beta, Gamma rays on youtube
radioactive dating using Uranium on Youtube
Animation Explain Why Nuclear decay and emissions occurs
One Half-life to Live Song on Youtube

3. Lesson 1: Nuclear Radioactivity:
Nucleus- composed of protons and neutrons
Strong Force – causes protons and neutrons to be attracted to each other

4. Powerful only when protons and neutrons closely packed together
Large nucleus – held less tightly
Small nucleus – held tightly

5. Radioactivity:
Nuclear Decay which happens when the strong force is not large enough to hold the nucleus together
Nucleus gives off matter and energy
unstable nuclei change by emitting particles & releasing energy until they transform into a different isotope or another element

6. Side Note:
Isotopes
Remember: isotopes are atoms with the same number of protons, but different number of neutrons
C-14 6 protons, 8 neutrons
C-12 6 protons, 6 neutrons

7. Stability
An atoms stability will depend on a ratio or comparison of protons to neutrons in the nucleus
Ideal ratio:
For light elements  1:1 ratio
For heavy elements  3:2 ratio of neutrons to protons

8. A nucleus with either too many or to few neutrons compared to protons is radioactive

9. Predict if the following Isotopes are stable or unstable?
Boron-12
Oxygen 16
Carbon – 14
Carbon - 12
Magnesium – 22
Sodium- 23
Phosphorus – 32
Aluminum – 27

10. History:
1896 – Henri Becquerel discovered radioactivity with the element Uranium

11. 1898 – Marie and Pierre Curie discovered radioactive Polonium and Radium
Nobel Prize in 1903
First woman to win Nobel Prize
1911 Marie Curie won 2nd Nobel Prize
First person to win 2nd Nobel Prize

12. Explain why nuclear decay occurs.
Exit Slip
Explain why nuclear decay occurs.

13. Lesson 2: Nuclear Decay
Nuclear Radiation - Particles and energy released from decaying nucleus
3 types:
Alpha particles (a)
Beta particles (b)
Gamma rays (g)

14. Alpha Particles
particle that consists of two protons and two neutrons with an electric charge of +2
Like a Helium nucleus

15. Alpha Particles do not travel far due to:
Massive size
Leave charged ions in the path when they travel through matter due to stripping off electrons
Are the least penetrating form of nuclear radiation
Can cause serious biological damage

18. Beta Particles (b):
electron emitted during the radioactive decay of a neutron into a proton in an unstable nucleus

19. Beta Particles (b):
travels further through matter than alpha particles
fast moving because it is so small

21. Gamma Rays (g):
high energy electromagnetic radiation emitted by a nucleus during radioactive decay

22. Gamma Rays (g): Have no mass and no charge
can penetrate matter deeply (up to 7 cm of Pb), even buildings
radon (discovered by the Curie’s) was found to emit these types of rays by Paul Villard in 1900

24. Background radiation
Low level radiation emitted mainly by naturally occurring radioactive isotopes found in the Earth’s rocks, soils, atmosphere

25. Background radiation
Largest source (54%) is Radon gas produced in earth’s crust
From cosmic rays (8%)
From radioactive isotopes in the body (11%)

26. Radon Gas produced by Decay of Uranium-238 in earth’s curst

29. Estimate Your Personal Radiation Dose

30. Where you live Cosmic radiation:
At sea level mrem ft
ft ft
ft ft
ft ft
ft ft

31. Terrestrial (from the ground):
If you live in a state that borders the Gulf or Atlantic Coasts, add 16 mrem
If you live in the Colorado Plateau area (around Denver), add 63 mrem
If you live anywhere else in the continental US, add 30 mrem.

32. House Construction:
If you live in a stone, adobe, brick, or concrete building, add 7 mrem
Power Plants:
If you live within 50 miles of a nuclear power plant, add 0.01 mrem
If you live within 50 miles of a coal-fired power plant, add 0.03 mrem

33. From air (radon), everyone add 200 mrem
Food, Water, and Air
Internal Radiation:
From food (Carbon-14 and Potassium-40) & from water (radon dissolved in water), everyone add 40 mrem
From air (radon), everyone add 200 mrem

34. How You Live: Weapons test fallout (less than 1)..1 mrem
Jet Plane Travel (per hour in the air) ……………0.05 mrem
Have porcelain crowns or false teeth ………………0.07 mrem
Weat a luminous wristwatch mrem
If you go through luggage inspection at airport ……………… mrem

35. If you watch TV mrem
If you use video display terminal (computer screen)……………….1 mrem
Have a smoke detector…… mrem
Use a gas camping lantern…….0.2 mrem
If you wear a plutonium-powered pacemaker …………….100 mrem

36. Extremity (arm, hand, foot, or leg)....1 Dental....1 Chest....6
Medical Tests
Medical Diagnostic Tests-Number of millirems per procedure
X-Rays:
Extremity (arm, hand, foot, or leg)....1
Dental Chest....6
pelvis/hip Skull/neck...20
Barium enema Upper GI
CAT Scan (head and body)
Nuclear Medicine (e.g., thyroid scan)

37. What is your total?
Add them all up to get your Estimated Annual Radiation Dose
Write a statement about How your dose compares to the average dose per person of 360 mrems per year?

38. Lesson 3: Transmutation
Process of one element’s changing to another through nuclear decay

40. Solving Nuclear Equations:
A nuclear equation shows how a nucleus gains or loses subatomic particles.
Ex. 1:
11H + 94Be ---> 63Li + 42He
Rule: The sum of the mass numbers of the reactants equals the sum of the mass numbers of the products .

41. What is the missing part of this equation?
2713Al + ?? ---> 3015P + 10n
42He

42. Solve this one:
? + 0-1e --> 24494Pu
24493Np

45. Lesson 4: Half-life of radioactive Isotopes
The length of time it takes half of the atoms of a sample of the radioactive isotope to decay
Vary from fractions of a second to billions of years

46. Radioactive Decay Rates
Radioactive decay is used to determine the age of old objects.
Carbon-14 dating can be used to date once-living materials from the past 50,000 years
Uranium dating cam be used to date rocks

50. Radioactive Decay Series for I-131

51. Radioactive Decay Series for I-131
Original sample

52. Radioactive Decay Series for I-131
1- half life

53. Radioactive Decay Series for I-131
2 – half lifes

54. Radioactive Decay Series for I-131
3 – half lives

55. Isotope Half - life Examples of Half-lifes for different Isotopes
K-40 1,280,000,000 years
Pt ,120 years
I days
Th s

57. Detecting Radioactivity
Radiation Detectors are Instruments used to identify ions formed when radiation passes through matter
Cloud Chamber
Bubble Chamber
Electroscope
Geiger counter

58. Bubble Chamber

59. Lesson 5: Nuclear Reactions: Nuclear fission
process of splitting a nucleus into two nuclei with smaller masses

60. Nuclear fission a large amount of energy is released
Used in Nuclear reactors in power plants and submarines

61. Historical Events:
1938 Otto Hahn and Fritz Strassmann discovered the that a nucleus could be split
 struck U-235 with a neutron nucleus split into smaller nuclei

62. 1939 Lise Meitner Theorized this process as “Nuclear Fission”
Coined the term “Fission”
She had worked with Hahn before fleeing Nazi Germany

63. Historical Events:
Dec 2nd, 1942 – Team lead by Enrico Fermi initiates the First Nuclear Chain Reaction
Known as “Manhattan Project”

64. Chain reaction – an ongoing series of Fission reactions

76. Animation Controlled/Uncontrolled Reation
Critical Mass – amount of fissionable material required to continue a reaction at a constant rate
Control Rods – used in nuclear reactors to absorb neutrons to control the rate of the fission reaction
Animation Controlled/Uncontrolled Reation

77. Fission Q: Can chain reactions always be controlled?
A: Somewhat, but only if materials are used to absorb some of the neutrons
Uses of chain reactions:
1. controlled: to generate electricity
2. not controlled: nuclear bomb

78. Nuclar Fusion
Two nuclei with low masses are combined to form one nucleus of larger mass

79. Can only happen when nuclei are moving fast enough to get close to each other
Temperature in stars (millions of °C) are high enough for fusion to occur

80. It is very difficult to contain the reaction.
it must happen at temperatures greater than 108 oC,
no known material could contain it without melting
some success has been achieved by containing the reaction in a magnetic field

81. Dangers and Benefits of Nuclear Radiation
Radioactive substances can be very useful , but when used carelessly, nuclear radiation can be extremely dangerous, even though we are exposed to some radiation everyday.

82. Dangers from Nuclear Radiation
Background radiation
causing radiation sickness
causing genetic mutations

83. Benefits from Nuclear Radiation
smoke detectors
radioactive tracers in medicine
radioactive material added to a substance so that its location can be detected later

84. Irradiation of Food
Radiation Therapy for the Treatment of Cancer

85. Benefits to Nuclear Power
does not produce gaseous pollutants that cause ozone depletion and acid rain
Cheap to make electricity this way but expensive to build the power plant
More energy in the known uranium reserves than in the known reserves of coal and oil

86. Dangers to Nuclear Power
Radioactive products must be handled correctly
Safety of the reactors
Equip with shielding
Storage of spent nuclear fuel

87. Countries Generating Most Nuclear Power
Country
Total MW
USA
99,784
France
58,493
Japan
38,875
Germany
22,657
Russia
19,843
Canada
15,755
Ukraine
12,679
United Kingdom
11,720
Sweden
10,002
South Korea
8,170

88. States with nuclear power plant(s)

89. World Nuclear Reactors

90. Nuclear Fuel Cycle

92. U-235 U-238 Plutonium-239 Uranium enrichment Fissionable at 3%
Weapons grade at 90%
U-238
More stable
Plutonium-239
Created from U-238; highly radioactive

93. Nuclear Power

94. Nuclear Reactor Structure
Reactor’s pressure vessel typically housed in 8” of steel
36” concrete shielding
45” steel reinforced concrete

96. Risks of enrichment and fuel fabrication
Largest industrial users of water, electricity
Paducah, KY, Oak Ridge, TN, Portsmouth, OH
Cancers and leukemia among workers
Fires and mass exposure.
Karen Silkwood at Oklahoma fabrication plant.
Risk of theft of bomb material.

97. Nuclear Reactor Process
3% enriched Uranium pellets formed into rods, which are formed into bundles
Bundles submerged in water coolant inside pressure vessel, with control rods.
Bundles must be SUPERCRITICAL; will overheat and melt if no control rods. Reaction converts water to steam, which powers steam turbine

98. Other reactor accidents (besides TMI and Chernobyl)
1952 Chalk River, Ontario
Partial core meltdown
1957 Windscale, England
Graphite reactor fire contaminates 200 square miles.
1975 Browns Ferry, Alabama
Plant caught fire
1976 Lubmin, East Germany
Near meltdown of reactor core .
1999 Tokaimura, Japan
Nuclear fuel plant spewed high levels of radioactive gas

100. United States

101. Risk of terrorism (new challenge to industry)
9/11 jet
passed near
Indian Point
Risk of terrorism (new challenge to industry)

103. Reprocessing Separates reusable fuel from waste 1960s West Valley, NY
Large amounts of radioactivity released
1960s West Valley, NY
Radiation leaked into Lake Ontario
1970s La Hague, France
Released plutonium plumes into air

104. Back end: Radioactive wastes
Low-level wastes in commercial facilities
Spent fuel in pools or “dry casks” by plants
Nuclear lab wastes
Hanford wastes leaked radiation into Columbia River
High-level underground repository
Yucca Mountain in Nevada to 2037
Wolf River Batholith in Wisconsin after 2037?
Risks of cracks in bedrock, water seepage

106. Yucca Mountain

107. Transportation risks Uranium oxide spills Fuel rod spills (WI 1981)
Radioactive waste risks

108. “Mobile Chernobyl” to Yucca Mtn.

109. Kyshtym waste disaster, 1957
Orphans
Explosion at Soviet weapons factory forces evacuation of over 10,000 people in Ural Mts.
Area size of Rhode Island still uninhabited; thousands of cancers reported

111. Radioactive Waste Recycling
Disposal of radioactive waste from nuclear power plants and weapons facilities by recycling it into household products.
In 1996, 15,000 tons of metal were received by the Association of Radioactive Metal Recyclers . Much was recycled into products without consumer knowledge.
Depleted Uranium munitions for military.

112. Summary Nuclear energy has no typical pollutants or greenhouse gasses
Nuclear waste contains high levels of radioactive waste, which are active for hundreds of thousands of years.
The controversy around nuclear energy stems from all parts of the nuclear chain.