Describe nuclear fission. What happens to the atomic number, mass number, protons, neutrons? Be able to write the reaction equation.
Nuclear fission is a nuclear reaction in which a heavy atomic nucleus, typically uranium-235 or plutonium-239, is split into two or more lighter nuclei, accompanied by the release of a large amount of energy. This process is generally induced by bombarding the nucleus with a neutron.
During nuclear fission, the atomic number and mass number of the original nucleus are both conserved. However, the atomic number of the resulting nuclei is different, as they are typically lighter due to the splitting of the nucleus. The total number of protons and neutrons in the original nucleus will be divided between the resulting nuclei.
The reaction equation for nuclear fission is typically represented as follows:
original nucleus + neutron → lighter nucleus + lighter nucleus + additional neutrons + energy
For instance, a common example of nuclear fission involves the reaction of uranium-235 with a neutron:
U-235 + n → Ba-141 + Kr-92 + 3n
In this reaction, a uranium-235 nucleus absorbs a neutron, resulting in the formation of barium-141, krypton-92, and the ejection of three additional neutrons. Along with the creation of these nuclei, a substantial amount of energy is released.
Describe nuclear fusion. What happens to the atomic number, mass number, protons, neutrons? Be able to write the reaction equation.
Nuclear fusion is a nuclear reaction in which two or more atomic nuclei fuse together to form a heavier nucleus. This process releases a tremendous amount of energy and is the fundamental power source of stars like the Sun. Nuclear fusion requires extremely high temperatures and pressures to overcome the electrostatic repulsion between positively charged atomic nuclei.
During nuclear fusion, the atomic number and mass number of the original nuclei combine to form the atomic number and mass number of the resulting nucleus. The total number of protons and neutrons in the original nuclei adds up to the total number of protons and neutrons in the resulting nucleus.
The reaction equation for nuclear fusion involves the addition of reactant nuclei, fusion, and the release of energy. It can vary depending on the specific elements involved. One example is the fusion reaction that occurs in the Sun, where hydrogen nuclei (protons) combine to form helium:
4H → He + energy
In this equation, four hydrogen nuclei (protons) combine to form helium, releasing a significant amount of energy in the process. This fusion reaction occurs through a series of intermediate steps involving the conversion of hydrogen into deuterium and the subsequent fusion of deuterium nuclei to form helium. The net result is the conversion of hydrogen into helium, along with the release of a huge amount of energy.