Fusion and fission are two distinct nuclear changes with significant differences in their underlying processes and outcomes. Fusion involves the merging of two lighter atomic nuclei to form a heavier nucleus, releasing a tremendous amount of energy in the process. This phenomenon occurs at extremely high temperatures and pressures, typically found in the core of stars, where hydrogen nuclei combine to form helium through the proton-proton chain. A real-world example of fusion is the process taking place in the Sun, where hydrogen nuclei fuse together to produce helium, releasing vast amounts of energy in the form of light and heat.
On the other hand, fission is the splitting of a heavy atomic nucleus into two or more smaller nuclei along with the release of a large amount of energy. This process can be induced by bombarding the nucleus with neutrons, and it is commonly used in nuclear power plants to generate electricity. A practical example of fission is the nuclear fission of uranium-235 in a controlled chain reaction within a nuclear reactor. When a neutron collides with a uranium-235 nucleus, it splits into two smaller nuclei (e.g., xenon-135 and strontium-99) and releases more neutrons, which can trigger a chain reaction, resulting in the release of a significant amount of energy used to produce electricity.
