Both fusion and fission reactions are very critical for our lives. These two reactions are involved in star burning reactions to sun glowing processes. Nuclear fusion is one category of nuclear reaction. Nuclear fusion is a process through which two or more nuclei of light elements are combined to form heavier elements leading to the release of an excessive amount of energy.
Nuclear fission is the process in which the nucleus splits into smaller nuclei. Fission processes are widely used in nuclear power reactors, and uranium atoms are commonly used. A neutron strikes with a uranium atom and divides into smaller nuclei during nuclear fission. A tremendous quantity of energy in the form of heat and radiation is released. Fission reactions are further divided into two types: spontaneous and induced fission.
When a nucleus like uranium tends to fission and capture a neutron, it enters an unstable system and finally breaks into two heavy components, induced fission. It also emits neutrons during this process.
Nuclear Fission: Process
Nuclear fission is a reaction in which a heavy nucleus containing atoms is struck by neutrons and becomes unstable. This led to the decomposition of heavy nuclei into two nuclei with equal quantity and magnitude, releasing a large amount of energy and two or three neutrons.
These neutrons can trigger other fissions by interacting with new nuclear fission nuclei, emitting more neutrons. The phenomenon of multiplication of nuclei is known as a Chain reaction. The amount of fissioned nuclei releases a million times more energy in a fraction of a second than burning a block of carbon or bursting a block of dynamite of the same mass. Energy is released significantly faster in a nuclear reaction than in a chemical reaction due to the speed of the reaction process.
The number of fissions every second will be limited if just one of the released neutrons may be used to cause subsequent fission. Nuclear reactors, which are regulated sources of nuclear fission energy, work on this concept.
Nuclear Fission Reactors
Nuclear fission is a powerful source of energy. A chain reaction is required to produce output energy or power flow. In a fission reactor, a nuclear chain reaction takes the following form: n + X —> Y + Z + fast neutrons.
A fissionable nucleus indicated by X catches an inactive neutron (n). Active neutrons are emitted when X fissions into two lighter but more firmly linked nuclei, Y and Z. For chain reactions to proceed, a reactor must have plenty of supply of fissionable material. Subcritical material is defined as having insufficient fissionable material to maintain a chain reaction. A moderator, usually water, is utilised in the reactor to slow down the rapid neutrons and make them easier to absorb so that the chain reaction can be controlled.
The kinetic energy of the neutrons produced by the chain reaction is used to heat water, create steam, and drive a generator that generates electricity in a standard nuclear fission reactor.
Distinguish between Nuclear fusion and fission
Nuclear fission | Nuclear fusion |
Nuclei of heavy elements are involved in it. | Nuclei of light elements are involved in it. |
The process through which a heavy nucleus splits into lighter nuclei. | The process through which lighter nuclei combine to form heavy nuclei. |
Ordinary temperature can be used in it. | Only higher temperature supports this reaction (108°C). |
The amount of energy released in this process is very high. | The amount of energy liberated in this is comparatively low. |
Energy conversion efficiency is less. | Energy conversion efficiency is high (four times higher than the fission reaction). |
With useful tools and strategies, the process can be controlled. | The process is uncontrollable. |
Nuclear Fission: Harmful Effects
There are a few cons to nuclear fission, they are:
- Fission generates hazardous waste that must be stored.
- Fissionable material is in short supply, but breeder reactors that produce fissionable material may be a viable alternative.
- The spread of fissionable material raises the risk of nuclear weapons being out of control.
Nuclear Fission: Useful Effects
- Nuclear fission helps in generating electricity. Electricity holds much importance in our daily lives. Almost everything we use requires electricity.
- Electricity generation results in emission that is harmful to the environment; however, with the help of nuclear fission, it is possible to create electricity without affecting the environment. In this, steam is produced during nuclear fission to rotate the turbine for generating electricity. This is sustainable and better for the environment.
Conclusion
To conclude what we have learned till now, we know that nuclear fission is the splitting of an atom’s nucleus into multiple smaller nuclei referred to as fission products. When the heavy atoms go through nuclear fission, this is known as an exothermic reaction that releases enormous amounts of energy.
Nuclear fission occurs when the electromagnetic force pushing the nucleus apart overcomes the strong nuclear force holding it together with heavier atoms. As a result, nuclear power helps protect the environment by generating large amounts of carbon-free electricity.