Comprehensive Study Guide on Nuclear Fission and Fusion

Definition and General Process: Nuclear fission is the process of splitting large, heavy atoms into smaller elements. This occurs when a neutron collides with the nucleus of a large atom.
Primary Elements Involved: The most common elements associated with nuclear fission are Uranium ( ${}^{235}\text{U}$ ) and Plutonium ( $\text{Pu}$ ). The mention of these elements in a scientific context typically signifies a fission-related problem.
The Reaction Mechanism:
- A high-speed neutron is directed to collide perfectly with a large, unstable nucleus.
- The collision cause the large atom to split into two or more smaller elements (atoms).
- This process releases additional neutrons (typically two or three) and a crack ton of energy in a very short amount of time.
Chain Reactions: Fission is characterized as a self-sustaining sequence known as a chain reaction.
- The neutrons released from the initial split go on to collide with other nearby large atoms.
- This secondary collision causes those atoms to split, releasing even more neutrons and energy.
- This exponential expansion continues, creating a massive release of power.

Nuclear Power Plants: Fission is the primary process used in nuclear power plants to generate electricity. It provides a significant source of energy that does not rely on fossil fuels.
Military Applications:
- The technology was utilized in the development of atomic bombs during World War 2 ( $\text{WWII}$ ).
- Currently, all global superpowers possess nuclear weapons with enough power to cause catastrophic destruction.
- Mutually Assured Destruction (MAD): This is a geopolitical doctrine where superpowers possess weapons so powerful (capable of destroying large portions of the Earth's mass or knocking it out of orbit) that no one dares use them. If one power utilizes a bomb, the other responds in kind, leading to the end of life on Earth.

Uranium-235 ( ${}^{235}\text{U}$ ): This is the specific isotope required for fission. It is extremely rare, making up only about half of one percent ( $0.5\%$ ) of all uranium found on Earth.
Uranium-238 ( ${}^{235}\text{U}$ ): The vast majority of naturally occurring uranium is ${}^{238}\text{U}$ . This isotope is nonfissionable, meaning it cannot be used for nuclear reactions in its natural state.
Enrichment: This is the man-made process of attempting to convert nonfissionable ${}^{238}\text{U}$ into the fissionable ${}^{235}\text{U}$ .
- It is a very difficult, time-consuming, and expensive process requiring vast amounts of energy and power.
- Enrichment is often a point of international concern, as seen in news regarding countries like Iran trying to enrich uranium for potential weaponization.

Radioactive Waste: The end products of fission are dangerously radioactive and chemically toxic.
Waste Disposal Issues:
- There is no way to make nuclear waste vanish; it must be stored somewhere on Earth.
- Historically, waste was often dumped into waterways. For example, power plants in Oswego (located on Lake Ontario) previously dumped radioactive waste directly into the lake.
Case Study: Aero Drive: Located near an airport, a fenced-off area with mounds of grass on a road called Aero Drive serves as a burial site for nuclear waste from the Oswego power plant.
- The waste was placed slightly below ground and covered with dirt.
- Recent lawsuits have revealed that radioactivity from such sites can leak into the water tables and cause runoff, which is highly detrimental to the environment.

Definition: Fusion is the opposite of fission. It involves combining smaller nuclei to form a single nucleus of greater mass.
Natural Occurrence: Fusion is the process that powers the sun and other stars.
Elemental Components: In fusion, the most common elements involved are Hydrogen ( $\text{H}$ ) and Helium ( $\text{He}$ ).
- A common reaction involves fusing two hydrogen atoms to create a helium atom.
- This process releases a neutron and a massive amount of energy while conserving mass.
The Origin of Matter: Stars are the "factories" where all elements in the universe are created through fusion. Humans are comprised of roughly $98\%$ "CHONP" elements: Carbon ( $\text{C}$ ), Hydrogen ( $\text{H}$ ), Oxygen ( $\text{O}$ ), Nitrogen ( $\text{N}$ ), and Phosphorus ( $\text{P}$ ). All of these elements originated from stars that exploded.

Extreme Requirements: Fusion requires extremely high temperatures and high pressure to occur.
- Scientists estimate that temperatures must reach approximately $15,000,000\,^{\circ}\text{C}$ (fifteen million degrees Celsius).
Containment Issues: Currently, there is no material on Earth capable of creating a container that can withstand and contain the heat and pressure necessary for a sustained fusion reaction.
The Goal of Sustainable Fusion: If scientists can recreate fusion on Earth, it would provide several transformative benefits:
- An infinite amount of usable energy.
- Absolutely no radioactive waste products or byproducts.
- Extremely low costs since the fuel (Hydrogen and Helium) is very common and cheap.
Current Research: Scientists are currently attempting to find ways to facilitate "low-temperature" fusion reactions to bypass the containment issues of high-temperature reactions. Any individual who successfully develops this technology would likely become a trillionaire due to the shift in global energy economics.