difference between nuclear fission and nuclear fusion with example

Nuclear Fission

1. Definition: Nuclear fission is a nuclear reaction in which the nucleus of an atom splits into two or more smaller nuclei, along with the release of a significant amount of energy.

2. Process: In nuclear fission, a heavy nucleus, such as that of uranium-235 (U-235) or plutonium-239 (Pu-239), absorbs a neutron and becomes unstable. The nucleus then undergoes a process of splitting into two or more smaller nuclei, releasing additional neutrons and a substantial amount of energy in the form of heat.

3. Energy Source: Nuclear fission is the process that powers nuclear reactors and atomic bombs. In nuclear power plants, controlled fission reactions are used to generate heat, which is then converted into electricity.

4. Example: In a nuclear power plant, U-235 nuclei are bombarded with neutrons. When a U-235 nucleus absorbs a neutron, it becomes U-236, which is highly unstable and quickly splits into smaller nuclei, such as krypton-92 and barium-141, along with the release of energy and additional neutrons.

Nuclear Fusion

1. Definition: Nuclear fusion is a nuclear reaction in which two or more light nuclei combine to form a heavier nucleus, accompanied by the release of a significant amount of energy.

2. Process: In nuclear fusion, typically at extremely high temperatures and pressures, light nuclei, such as isotopes of hydrogen (e.g., deuterium and tritium), come together to form a heavier nucleus. This process results in the release of energy and the formation of a new element.

3. Energy Source: Nuclear fusion is the process that powers the sun and other stars. Scientists are also working on controlled nuclear fusion as a potential future energy source on Earth. Achieving controlled nuclear fusion on Earth could provide a nearly limitless and clean source of energy.

4. Example: In the sun, the primary fusion process involves the combination of hydrogen nuclei (protons) to form helium nuclei. Four hydrogen nuclei (protons) come together to produce a helium nucleus (two protons and two neutrons), releasing a tremendous amount of energy in the form of light and heat.

Key Differences

• Reaction Type: Fission involves the splitting of heavy nuclei into smaller ones, while fusion involves the combining of light nuclei to form a heavier one.

• Energy Release: Both fission and fusion release a significant amount of energy, but fusion releases even more energy per unit mass than fission.

• Fuel: Fission typically uses heavy nuclei like uranium or plutonium as fuel, while fusion uses light nuclei like isotopes of hydrogen.

• Applications: Fission is currently used in nuclear reactors for power generation and in atomic bombs, while controlled fusion is still under development for potential future energy production.

• Waste: Fission produces radioactive waste that needs to be managed and stored, while fusion would produce minimal long-lived radioactive waste if successfully harnessed for energy production.