1. Warm-up
Sodium-24 beta decays. What new isotope is formed when it decays?
How much new isotope is formed after 45 hours of a decaying Na-24?
How much old isotope is left after 45 hours?
How much C-14 is left after 11,400 years?
How much old isotope is left after 5 half lives?

2. Warm-up Write alpha, beta and electron capture decay Rx for Na-24
Draw the shift in #p+ and #no into the graph below using arrows marked with the decay symbol
#no
X Na-24
#p+

3. 25.2
Radiation in your life

4. Nuclear Fission Fission = splitting (of a nucleus)
creates a chain reaction of high speed neutrons that split more nuclei
generates enormous
amounts of energy

5. 2 Types of Fission uncontrolled nuclear reaction – A Bomb
controlled nuclear reaction – nuclear power plant

6. Controlled Nuclear Fission
Speed of the neutrons is lowered by graphite rods
The coolant is heated that power steam turbines to generate electricity

7. Nuclear Reactor

8. How does a Nuclear PP works
NPP
san onofre

9. Below are arguments pro/against Nuclear Energy
Forever storage of nuclear waste
no pollution, greenhouse gas emission (CO2)
Accidents that can lead to widespread contaminations (Three Mile Island, Chernobyl, Fukoshima)
independence from oil (political costs…)
long term, large scale, reliable energy production

10. Nuclear Fusion Fusion: combining (two small nuclei)
more energy than nuclear fission
Also creates a chain reaction
Sun does nuclear fusion

11. Nuclear Fusion life nf

12. Forces Within the Nucleus
Electromagnetic repulsion:
Protons repelling each other
Nuclear forces: neutrons and nuclear binding energy glue protons together “cosmic glue”
Nuclear forces > electromagnetic repulsion, element is stable
Nuclear forces < electromagnetic repulsion, radioisotope

13. Ionizing Radiation
Radiation with enough energy to knock electrons of the exposed elements and change them
Formation of ions – charged atoms (#p+ and e- is not equal!!!)
Particle radiation: alpha and beta particles
Electromagnetic waves: UV, X-rays, gamma rays

14. Electromagnetic Spectrum

15. DNA Damage from Radiation

16. Dose vs Damage -radiation doses are measured in Sieverts

19. radiation
cellphones and tumors

20. Nuclear Medicine
Radiation treatment of cancer. Radiation affects quickly dividing cells more than non-dividing cells (normal)
Injection of Iodine-131 for the detection of thyroid function:

21. Research
Radiolabeling of molecules, cell parts with radioisotopes H-3, S-35…

22. Fossil dating
When the animal is alive it incorporates radioactive trace elements from environment
Example: C-14 alongside C-13, C-12
T1/2 = 5700 years
When animal dies/fossilizes C-14 is not replaced but undergoes transmutation to N-14.
What type of transmutation turns C-14 into N-14?
The older the fossil the more C-14 is gone

23. Half-life of selected isotopes
Bismuth sec
Sodium hours
Iodine days
Hydrogen years
Cobalt years
Carbon years
Uranium billion years

24. Half-life curve

25. Warm-up
Sketch the reactor of a nuclear power plant, label the parts and explain their function