1. Nuclear Energy

3. Nuclear Energy comes from the nuclei of atoms Nuclear Energy can be Produced Through Nuclear Fusion and Nuclear Fission

4. Nuclear Fusion
The combining of 2 smaller nuclei to make 1 large nucleus
Ex) Sun (star)  heat from the sun is
produced by fusion
H + H  He + Energy

5. Why is Nuclear Fusion not used as an Energy Source?
3 Problems
1) High Temperature
 must approach that of the center of the sun
Container problem
2) Adequate Density of Hydrogen (H)
3) Confinement
 Remember: H is basically a proton,
like charges want to repel

6. Due to these Problems Nuclear Fission has been more fully researched

7. History of Nuclear Energy
In 1938, the 1st controlled fission (atom splitting) of an atom occurred.
The energy of an atom was first researched to develop the nuclear bomb
The two cities hit were Nagasaki and Hiroshima

8. Parts of an Atom 1) Nucleus- central area *Protons = positive charge
2) Outside the nucleus
*Protons = positive
charge
*Neutron = neutral or
0 charge
A huge amt of E needed to hold nucleus together since protons repel
*Electrons = negative
charge

9. Radioactive Elements Radioactive= the nucleus is unstable
and disintegrate releasing a great amt of E
Rates of disintegration is the same for any
given radioactive element. This rate is called
the Radioactive half-life.
The time it takes for ½ of the radioactive material to decompose.

10. Nuclear Fission releases radiation
Alpha Radiation
Beta Radiation
Made up of 2 neutrons
And 2 protons
Made up of electrons released
from the nucleus
Can travel through air
for ~3 feet
Can travel a few feet
Stopped by clothing
Can be stopped by a sheet
of paper

11. Gamma Radiation Radiation Facts
A type of electromagnetic
Radiation
(x-rays, light/radio waves)
Radiation Facts
Able to penetrate several
inches of cement
Beta and Gamma radiation
cause about the same amount
of biological damage
Alpha radiation can cause up
to 20X more damage than
beta or gamma.

12. Determining Radioactive Half – Life Example problem
How long would it take for 20 grams of C-14
to be reduced to 5 grams? (C-14= 5730 yrs)
20g
 5730yr
 10g
10g
 5730yr
 5g
11,460yr

13. How much Iodine-132 would be left after
9.6 hrs, if you started with 100grams?
(I-132=2.4hrs)
100g
 2.4hr
 50g
4.8hr
50g
 2.4hr
 25g
7.2hr
25g
 2.4hr
 12.5g
12.5g
 2.4hr
 6.25g
9.6hr

14. Homework Solving Radioactive Half-life Problems Begin in class
Use the examples if you need help!!!

15. Day 2 REVIEW What are the 3 parts of an atom?
What are their charges and where are they located?
What is nuclear fission/fusion?
Define ½ - life.

16. How is Energy Produced?

17. What is nuclear Fission?
Nuclear Fission is when a large atom is split
Fission = division

18. How does fission happen?
A large atom (U-235) is struck by a
slow moving neutron
When the nucleus splits energy is released along
with 3 neutrons

19. Nuclear Chain Reaction
When a slow moving neutron strikes a the nucleus
it splits emitting 2-3 neutrons and Energy
The neutrons released
Strike another nucleus
causing a chain reaction
THINK OF DOMINOS !!!!!

20. Transparency Worksheet 40 Nuclear Fission

21. Nuclear Reactors A device that allows for a control nuclear fission
chain reaction
U-235 is the radioactive element used to fuel the nuclear reactor

22. Parts of a Nuclear Reactor
Fuel rods - contain U-235
Control rods - made of cadmium or boron which
are nonfissionable (DO NOT SPLIT)
Absorb excess neutrons which will slow down the chain reaction
When the control rods are withdrawn more fission occurs increasing the amount of heat released

23. What is a Moderator?
Since only a slow moving neutron is able to split an atom, fuel rods are submerged under water. The energy of the fast moving neutron is transferred to the water increasing its temperature.
Since the water moderate the speed of the neutron it is called the moderator

24. How is Electricity produced Using Nuclear Fission different from coal burning? The only difference is the source of the heat!
Distribute ditto

25. Nuclear Fuel Cycle Begins with mining Uranium Ore
contains < 0.2% uranium by weight
After processing the final product contains 3% uranium
This is converted to a powder and then compacted into pellets and sealed into a 4 meter rod (fuel rod)
Distribute ditto Nuclear Fuel Cycle 38
After fission occurs the amt of U decreases

26. Nuclear Fuel Cycle Ditto

27. Remember that spent fuel rods contain 1% U-235
Remember that spent fuel rods contain 1% U That is still 500X’s that found in nature!!!

28. Remember!!!! A spent fuel rod still contains 1% U-235!!!!
That is 500 x’s the level found in nature!

29. Problems and Concerns About Nuclear Waste
EXPOSURE TO RADIATION
Radiation is converted to lower E forms when absorbed by matter
This conversion causes damage at the cellular level

30. Effects of Radiation Exposure
High Dose, short exposure
Leads to death
Occurs during nuclear bomb or meltdown

31. Low dose, High exposure Leads to mutation
If in reproductive cell = birth defects
--If in a body cell = cancer
Because mutation are
Permanent, the results of
Low level exposure may
result in cancer later in life

32. Radiation is measured in rems
Radiation is measured in rems. Rems measure the amount of biological damage to tissue caused by certain amounts of radiation
Ex 1) Nuclear Blast 100,000 rem death 2) X-rays 10,000rem coma 1,000 rem leukemia 10 rem embryo deformities 3) Natural Background rem

33. What are some sources of Background Radiation?
1) Cosmic Rays (sun)
2) Radioisotopes from the soil (Radon)

34. Radon

35. 3) Military uses – artillery
4) Storage facilities
5) Medicine

36. Some Exposure Can be Avoided
1) Choose whether to have diagnostic x-rays ex) dentist
2) Protect your home from Radon
3) Avoid going into the sun or use sun blockers
ex) Don’t use tanning booths

37. Disposing of Nuclear Waste
Originally spent fuel rods were to be recycled.
Due to the cost of recycling, U.S. chose to store the waste instead. (Yucca Mountain)

38. Homework
Nuclear Waste Disposal Where and How?

39. Permanent Storage Underground
Must be geologically stable
Ex) Salt Mines
WHY???

40. Steps to Store Radioactive Waste
1) Radioactive material would be enclosed in glass containers and sealed in thick stainless steel containers
2) due to the high temperature of the waste, the
containers would be stored above ground for
~ 10 years
3) After 10 years, the containers would be placed
600 meters underground

41. Why has the US limited their Nuclear Program?
Due to nuclear accidents in the 1970’s the US has slowed it nuclear program.

42. Case Studies Three-Mile Island, PA
In 1979, a cooling malfunction caused part of the core to melt in the # 2 reactor.
Some radioactive gas was released a couple of days after the accident, but not enough to cause any dose above background levels to local residents. 
There were no injuries or adverse health effects from the Three Mile Island accident. 
Caused U.S. to rethink Nuclear Energy

43. Chernobyl, Ukraine *occurred on 26 April 1986
*The explosion and fire threw hot particles of the nuclear fuel and also far more dangerous fission products, radioactive isotopes such as caesium-137, iodine-131, strontium-90 and other radionuclides, into the air

44. Nature is reclaiming Chernobyl

48. Affects of Radiation
FROG

51. Most Recent Nuclear Disaster Fukushima, Japan

52. Tsunami

54. Radioactive Plume in the Ocean

55. Beta Radiation Global Circulation

56. Should Nuclear Power Be Pursued?

57. U.S. Nuclear Plant Distribution

58. Global Nuclear Plant Distribution

59. What Do You Think?
Think about the Energy requirements needed to run a country.
Should nuclear Energy be a part of the Energy Equation?
Write a paragraph, support your position with evidence

60. The Affects of Nuclear War
Earth Normally
a) 31% of the sun’s radiation is reflected by Earth’s atmosphere
b) 26% is absorbed by the atmosphere
c) 43% is absorbed by the Earth’s Surface

61. After a Nuclear War
Nuclear blasts would place a huge amount of particulates (smoke/dust) into the atmosphere
a) only 20% of the sun’s energy would be reflected by the
Earth’s atmosphere
b) 75% would be absorbed by the atmosphere
c) 5% would be absorbed by the Earth’s surface

62. Results of Nuclear War Nuclear Winter This would last several years!!
Decrease of temperature by 20-40o C within a few days
Plants die, due to lack of sunlight
Collapse of the food chain
This would last several years!!