What should I know?

1. Atoms are composed of a small dense nucleus made of neutrons and protons and a large region for electrons.

2. Atoms and particles naturally transition to more stable, less energetic states by shedding energy in the form of gamma rays or mass in the form of alpha or beta particles.

3. Radiation from radioactive sources can be detected through its interactions with its surroundings.

4. The types of radiation represent different changes in atoms, forming predictable chains of decay until a stable element is reached.

5. Specific radioactive atoms and particles will decay after a random interval, and so predictions about specific atoms and particles cannot be made. Instead, we can make a claim about the time required for half of the sample to decay, called the half-life.

6. Specific radioactive atoms and particles will decay after a random interval, and so predictions about specific atoms and particles cannot be made. Instead, we can make a claim about the time required for half of the sample to decay, called the half-life.

7. With a knowledge of the average time for an unstable sample to experience a decay of 50% of its particles -- called a half-life -- samples may be dated through an analysis of the quantity of remaining particles of that isotope.

8. "The breakdown of large, unstable nuclei into smaller nuclei is called fission. It is accompanied by the release of both particles and energy. 

9. Under the right conditions, the particles produced in the fission process can cause fission in other atoms, which, in turn will emit particles that cause fission in other atoms. This self-sustaining process is called a chain reaction. Chain reactions govern the behavior of atomic bombs and fission power plants."

10. Some of the mass released in the fission process becomes energy, which is used to heat water, which turns a turbine. The turbine converts energy of motion into electric current.

11. Einstein's most famous equation is E = mc^2. It makes the bold claim that particles can be thought of as massive amounts of captured and bound energy. This claim is the foundation for both radioactivity, fission and fusion processes.

12. The formation of larger nuclei from smaller also releases energy and emits particles. This process is the mechanism of heat production in stars and is also under development for energy production by humans.