1. From unstable to stable
Radioactivity
From unstable to stable

2. A few key Terms to know
Isotopes - atoms of the same element with different mass numbers (different numbers of neutrons)
Radioisotopes - isotopes of an element that are unstable
Radioactive decay – the process through which an unstable nucleus changes into another more stable nucleus
Radiation – energy that can be transmitted through a vacuum in the form of a wave
Examples: light, X-Rays, UV Rays, IR Rays, Gamma Rays, Radio Waves
Half-life - The amount of time it takes for one- half of a given mass or number of atoms to decay

3. Nuclear reactions
Chemical reactions involve changes in the electrons surrounding an atom.
Nuclear reactions involve changes inside the nucleus of an atom.

4. Radioactive atom
Gives off energy or particles during decay to become stable

5. Nuclear Stability Isotopes Atoms DO NOT like to be unstable!
Similar elements but different atomic weight; change in number of neutrons
Generally unstable
Atoms DO NOT like to be unstable!
Unstable atoms are considered radioactive

6. What Makes Us Stable?
Correct ratio of neutrons to protons Ratio increases from 1:1 to 3:2 as elements get heavier

7. Superstable elements in pink Unstable/Radioactive elements in yellow

8. Nuclear Stability How do they achieve stability?
Undergo radioactive decay to achieve stability
Three main types of nuclear radiation
Alpha 
Beta 
Gamma 
Each form of radiation emits LARGE amounts of energy!

9. Nuclear Decay Alpha Decay ()
Large, positively charged particle (can be blocked by a sheet of paper
Lost 2 protons and 4 neutrons
Radioactive
Isotope
Stable
Atom
Alpha
Particle

10. What is alpha radiation?
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11. Nuclear Decay Beta Decay ()
Proton becomes a neutron or neutron becomes proton
Gives off beta particle (either an electron or positron)
Radioactive
Isotope
Stable
Atom
Beta
Particle

12. What is beta radiation?
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13. Nuclear Decay Gamma Decay ()
No gain or loss of proton or neutron; atom only gives off energy
Does not happen alone, occurs with either alpha or beta decay
Radioactive
Isotope
Stable
Atom
Gamma
Particle

14. Nuclear Radiation Question Time!
Identify the following types of nuclear decay

15. Nuclear Radiation

16. Nuclear Radiation

17. Review!
Alpha 
Beta 
Gamma 

18. Video review: Radiation and Radioactive Decay
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19. Applications of Nuclear Chemistry
How was Radiation Discovered?
Wilhelm Roentgen (1895) - discovered X-Rays
Henri Becquerel (1896) - found that Uranium emits radiation onto photographic film - X-Rays
Marie and Pierre Curie (early 1900’s) - found Radium (another radioactive element) and Polonium
Found it ionized air particles and made phosphorescent objects glow
Found that when radiation is emitted, other elements are then created
Also found radiation causes severe health effects (They both died of cancer)
Ernst Rutherford (1912) – gold foil experiment; discovered the nucleus

20. Video: Carbon Dating
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21. Nuclear Bombardment Reactions
Ernest Rutherford first did this in 1919
Particle Accelerator - Basic Idea: Particle accelerators use a series of magnets to create a path that the nuclei must follow (nuclei are positively-charged, so they interact with magnets).
When a collision is desired, the orientation of the magnets is changed to change the path of the nuclei; two types:
Linear Accelerator – straight path, particles can get to about 90% speed of light
Tevatron – “big donut”; only a few in the USA – 99% speed of light

22. CERN: Super Collider
/03/large-hadron-collider-cern-scientists-second-run- particle-accelerator-video

23. Nuclear Reactors Nuclear Reactors How Do Nuclear Power Plants Work?
What went wrong at Chernobyl?