APES nuclear fission and radioactive waste cheat sheet

Nuclear fission definition?

The process of splitting an atomic nucleus into smaller particles, releasing a large amount of energy.

Fission reaction example.

Uranium-235 + Neutron → Barium-144 + Krypton-89 + 3 Neutrons + Energy.

True or False: Fission is a fusion process.

False. Fission involves splitting nuclei, while fusion combines them.

What fuels are primarily used in fission?

Uranium-235 and Plutonium-239 are the main fuels for nuclear fission.

Fission chain reaction?

A self-sustaining series of reactions where released neutrons cause further fission events.

Cause → Effect: Neutron bombardment.

Cause: Neutron hits nucleus. Effect: Nucleus splits, releasing energy and more neutrons.

What is a critical mass?

The minimum amount of fissile material needed to sustain a chain reaction.

Difference between fission and fusion.

Fission splits large nuclei; fusion combines small nuclei. Fusion releases more energy.

Nuclear fission energy formula.

Energy released can be calculated using $\displaystyle E = mc^2$, where m is mass lost.

What is a moderator in fission?

A substance that slows down neutrons to sustain the fission reaction, e.g., water or graphite.

Main purpose of control rods?

To absorb neutrons and regulate the fission process to prevent overheating.

What happens during nuclear fission?

The nucleus splits, releasing energy, neutrons, and radiation, leading to new isotopes.

Fill in the blank: Fission occurs in __________ reactors.

Nuclear reactors, where controlled fission reactions are maintained.

True or False: All isotopes can undergo fission.

False. Only certain isotopes, like Uranium-235 and Plutonium-239, are fissile.

Fission products?

Include isotopes like Cesium-137, Strontium-90, which are radioactive and require management.

What is a nuclear reactor?

A device that initiates and controls nuclear fission to generate energy.

Types of radioactive waste?

High-level waste (HLW) - spent fuel, low-level waste (LLW) - contaminated materials, transuranic waste (TRU) - plutonium and other heavy isotopes.

True or false: All radioactive waste can be disposed of in landfills.

False. High-level waste requires specialized disposal methods due to its long-term hazards.

What is high-level radioactive waste (HLW)?

HLW is generated from nuclear reactors and must be managed with strict safety protocols due to its intense radioactivity.

Fill in the blank: The storage method for HLW is _____.

deep geological repositories.

Two disposal methods for radioactive waste?

1. Geological disposal 2. Surface storage

What does the Nuclear Waste Policy Act of 1982 establish?

It sets the framework for the management and disposal of nuclear waste in the U.S.

Cause → Effect: What happens if radioactive waste is improperly stored?

Leakage into the environment → contamination of soil and groundwater.

What is low-level radioactive waste (LLW)?

LLW includes items like clothing, tools, and filters that have low levels of radioactivity.

Regulatory body overseeing nuclear waste?

U.S. Nuclear Regulatory Commission (NRC) - ensures safety and compliance.

Difference between storage and disposal?

Storage is temporary; disposal is permanent. Storage holds waste until it can be disposed of safely.

True or false: Transuranic waste is safe for shallow land burial.

False. Transuranic waste is highly radioactive and requires deep geological disposal.

Example of high-level waste?

Spent nuclear fuel from reactors, requiring advanced containment methods.

What are the primary concerns with radioactive waste?

Long-lived isotopes, potential leakage, public health risks, environmental contamination.

Fill in the blank: _____ is a method of storing radioactive waste above ground.

Dry cask storage.

What regulations govern radioactive waste management?

The Resource Conservation and Recovery Act (RCRA) and the Atomic Energy Act (AEA).

Cause → Effect: Why is deep geological disposal important?

It isolates waste from humans and the environment for thousands of years.

Nuclear energy production's primary environmental impact?

Greenhouse gas emissions reduction - Nuclear energy produces minimal greenhouse gases compared to fossil fuels.

True or False: Nuclear plants contribute significantly to air pollution.

False - Nuclear plants emit very low levels of air pollutants compared to coal or gas plants.

Main consequence of radioactive waste?

Long-term environmental contamination and health risks due to radiation exposure.

Nuclear accidents impact on environment?

Severe ecological damage, contamination of land and water, long-term health effects for nearby populations.

Fill in the blank: Nuclear power plants require ___ for cooling.

large amounts of water, impacting local aquatic ecosystems.

Comparison: Nuclear vs. Coal

Nuclear: Low emissions. Coal: High CO2 and pollutants. Nuclear is cleaner.

Primary source of water pollution from nuclear energy?

Thermal pollution from heated water discharge affecting local aquatic life.

Decommissioning nuclear plants leads to?

Land restoration challenges and management of residual radioactive materials.

Environmental justice issues related to nuclear waste?

Localized waste disposal often affects marginalized communities disproportionately.

Cause → Effect: Nuclear fission reactions?

Cause: Splitting of uranium atoms. Effect: Release of energy and radioactive materials.

What is the significance of the half-life of radioactive waste?

Determines the time frame for safe disposal and environmental monitoring.

Impact of radiation on ecosystems?

Can cause mutations, reduced biodiversity, and altered species interactions.

True or False: Nuclear waste is harmless after a few years.

False - Some isotopes remain hazardous for thousands of years.

Main risk from spent fuel pools?

Potential for radiation leaks and contamination if not properly managed.

Environmental recovery time after nuclear accident?

Can take decades to centuries, depending on contamination levels.

Formula: Energy released in fission?

$\displaystyle E = mc^2$ - Energy equals mass times the speed of light squared.

Nuclear energy production statistic

Nuclear energy supplies about 20% of the electricity in the U.S.

What is a major advantage of nuclear energy?

Low greenhouse gas emissions compared to fossil fuels.

True or False: Nuclear energy is the most expensive energy source.

False - Nuclear has high upfront costs but low operational costs.

Compare nuclear energy to coal.

Nuclear: Low emissions, high energy density. Coal: High emissions, lower energy density.

Fill in the blank: The half-life of uranium-235 is ____ years.

700 million years.

Cause of nuclear fission:

Absorption of a neutron by a heavy nucleus.

Disadvantages of nuclear energy:

- Radioactive waste - Risk of accidents - High initial costs

Nuclear fusion vs nuclear fission:

Fusion combines nuclei; fission splits nuclei. Fusion has higher energy potential.

Formula for energy released in fission:

$\displaystyle E = mc^2$ where $\displaystyle E$ is energy, $\displaystyle m$ is mass lost.

What are common nuclear fuels?

Uranium-235 and Plutonium-239.

True or False: Nuclear plants contribute to air pollution.

False - They do not produce air pollutants during operation.

Nuclear energy production efficiency:

Nuclear plants have thermal efficiencies around 33-37%.

Comparative energy density: Nuclear vs. solar.

Nuclear: ~1 million times more energy dense than solar.

What is the main byproduct of nuclear fission?

Radioactive waste, including isotopes like cesium-137.

Economic comparison: Nuclear vs. natural gas.

Nuclear has higher upfront costs but can be more stable in long-term pricing.

Advantages of nuclear over fossil fuels:

- Reduced GHG emissions - Stable energy source - Less land use