What is a Nuclear Fusion Reaction?

Nuclear fusion reaction involves combining two atomic nuclei to form a single heavier one, releasing an enormous amount of energy.

What is a Nuclear Fusion Reaction?
Table of Contents

About Nuclear Fusion Reaction

 

  • Nuclear fusion reaction involves combining two atomic nuclei to form a single heavier one, releasing an enormous amount of energy.
  • Such reactions do not occur at room temperature and large amounts of energy are required to create conditions conducive to generating fusion-powered energy.
  • It is the same fundamental reaction that powers the sun and other stars.

 

What is Nuclear Fission?

  • Nuclear Fission is a type of nuclear reaction in which the nucleus of an atom is split into two or more smaller nuclei, along with the release of a significant amount of energy.
  • Process:
    • It occurs when a large, heavy atomic nucleus, typically of elements like uranium-235 or plutonium-239, absorbs a neutron.
    • The nucleus becomes unstable and splits into two or more smaller nuclei, releasing additional neutrons, gamma rays, and a vast amount of energy in the form of kinetic energy.
    • The additional neutrons can further cause fission in nearby nuclei, leading to a chain reaction.

 

Nuclear Reactors:

  • Nuclear fission is employed in nuclear reactors to generate electricity.
  • In these reactors, controlled fission reactions take place within fuel assemblies, typically using enriched uranium or plutonium.
  • The heat produced during fission is used to generate steam, which drives turbines to produce electricity.
  • Issues with Nuclear Fission Reactors:
    • Radioactive Waste: Nuclear fission produces radioactive waste that remains hazardous for thousands of years.
    • Nuclear Accidents: The potential for nuclear accidents, although rare, is a significant concern.
    • High Initial Costs: Building nuclear fission reactors involves substantial upfront costs, making it a capital-intensive energy option.
    • Limited Fuel Supply: Most nuclear fission reactors use enriched uranium as fuel, which is a finite resource. While there is plenty of uranium in the world, the high-grade, economically viable deposits are limited.
  • Advantages of Nuclear Fusion Reactors:
    • Nuclear Fusion produces more energy than fission does. This means that a given amount of fuel yields much greater amounts of energy with fusion than with fission.
    • It also doesn’t produce radioactive byproducts that need to be stored, or harmful carbon emissions; it simply produces inert helium and a neutron.
    • Unlimited Fuel supply:  The fuel to make fusion happen is simply heavy hydrogen atoms, which can be found in something that Earth has in abundance: seawater. No mining of uranium is required.
    • It is much safer than nuclear fission, since fusion can’t create runaway reactions.

 


Q1) What is Radioactivity?

Radioactivity is a natural phenomenon by which certain unstable atomic nuclei spontaneously decay, emitting radiation in the form of particles or electromagnetic waves. This process is a result of the fundamental forces and interactions within the atomic nucleus.

Source: Unleashing Limitless Energy: US Scientists Repeat Nuclear Fusion Breakthrough

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