Thermonuclear Reaction: Overview, Questions, Preparation

A thermonuclear reaction is a technique in which two small-size nuclei are clashed with each other to make a bigger and heavier, singular nuclei. As soon as the collision takes place, an extensive amount of energy is released. The plasmic reaction occurring in the sun is a typical example of this process. A thermonuclear reaction takes place in two ways, i.e. controlled and uncontrolled. As the name suggests, a reaction having a controlled amount of heat release is called a controlled reaction. In an uncontrolled form, the flow of energy is uncontrolled and destructive. Examples of uncontrolled energy are atom bombs and nuclear weapons, while in a controlled form, the flow of energy is constructed systematically. 

One of the major problems in carrying out a thermonuclear reaction or fusion is the confinement of hot plasma. The hot plasma is used in the process, but it should not be placed directly with any solid. The right way to contain the expansion of hot plasma can be achieved by placing it inside a vacuum. The plasma needs to be confined because it expands with the increase in temperature. Such confinements are shown below:

1. Gravitational confinement – Gravitational confinement is only found in stars because the mass of the gravitational confinement is large and heavy, making it harder to confine. One of the rare stars capable of this fusion is Red dwarfs, other stars like brown dwarfs can only produce lithium and deuterium.
2. Electrostatic confinements – Electrostatic confinement is used to confine the ions. It has a cathode wire within an anode cage. Positive ions attract the negative charge, and negatively charged ions attract towards positively charged ions.
3. Inertial confinement – Inertial confinement reacts at a very high temperature and pressure to force a rapid pulse of heat to the substance’s surface.
4. Magnetic confinement – Magnetic confinement is used in the charged particles flowing in the magnetic line.

In thermonuclear reactions, there are no chain reactions, and that is why they are easier to control and stop as and when required, unlike fission reactions. Fusion reactions are more popular and more used when compared with fission reactions.

However, this type of energy will vanish in the coming 20-25 years because to harness such kind of energy is hard and limited.

The chapter ‘Nuclear Physics’ holds a weightage of 5-6 marks per the CBSE guidelines. It consists of 2 objective type questions and one short question containing 3 marks. This topic is considered an important topic from the exam point of view.

• Explain the use of magnetic confinement.

It is used in the charged particles flowing across the magnetic line.

• Explain one challenge in thermonuclear reaction?

The containment of hot plasma is a significant challenge.

• Explain why thermonuclear reactions are easy to control.

There are no continuous chain reactions in thermonuclear bombardments, which is why they are easier to control.

Q: What is the right containment situation for hot plasma?

Q: How does extensive energy release?

Q: How many types of thermonuclear reactions are there?

Q: What are the examples of uncontrolled thermonuclear reactions?

Q: What are the examples of controlled thermonuclear reactions?