Problem 11 - A Complete Resource Book in Chemistry for JEE Main

Question

The element used for carrying out the nuclear reaction is (a) Thorium-232 (b) Uranium-238 (c) Plutonium-239 (d) Neptunium-293

Step-by-Step Solution

Answer

The element used is Plutonium-239 (c).

Step 1: Understanding Nuclear Reactions

In nuclear reactions, specific isotopes are used as fuel or for initiating reactions like fission or fusion. Isotopes with large atomic masses like Uranium-235, Uranium-238, and Plutonium-239 are commonly used.

Step 2: Identifying Common Nuclear Fuels

Uranium-235 and Plutonium-239 are well-known isotopes used in nuclear reactors and atomic bombs. Uranium-238, although abundant, is not directly fissile but can be converted into Plutonium-239 in reactors.

Step 3: Evaluating the Options

Evaluating the options given: (a) Thorium-232 is used in reactors but usually after conversion to Uranium-233, (b) Uranium-238 can be used for breeding Plutonium-239, (c) Plutonium-239 is a common fuel in nuclear reactors and weapons, and (d) Neptunium-293 is not commonly used due to its instability and other factors.

Step 4: Choosing the Correct Answer

Considering its frequent use in nuclear reactors and weapons, Plutonium-239 (option c) is a commonly used element for carrying out nuclear reactions.

Key Concepts

Nuclear Fuels

Nuclear fuels are materials that undergo fission to release energy. They are the heart of nuclear reactions, which occur in power plants or other nuclear facilities.
The process of fission splits an atom, releasing a significant amount of energy.
This transformation generates heat, which can be used to produce electricity. Common examples of nuclear fuels include:

• Uranium-235: A naturally occurring isotope used extensively in nuclear power plants.
• Plutonium-239: Formed from Uranium-238 in reactors, it's known for its efficiency in sustaining chain reactions.
• Thorium-232: Not fissile directly, but usable after conversion to other isotopes like Uranium-233.

Fuels are chosen based on availability, efficiency, and the type of nuclear reaction intended.
They are highly regulated to ensure safety and minimize environmental impact.

Isotopes

Isotopes are variants of elements that contain the same number of protons but a different number of neutrons.
This difference affects the atomic mass and properties without altering chemical behavior. Key points about isotopes:

• They are categorized based on their stability — stable or radioactive.
• In nuclear reactions, isotopes with large atomic masses often serve as fuel due to their ability to sustain fission.
• Examples include Uranium-235 and Plutonium-239, both vital in energy production and weaponry.

Understanding isotopes is crucial in nuclear science because each has unique properties impacting nuclear reaction processes.
Their behavior influences reaction dynamics and energy output.

Plutonium-239

Plutonium-239 is a pivotal isotope in nuclear reactions, valued for its capacity to sustain chain reactions and release vast amounts of energy.
It is formed primarily from Uranium-238 in nuclear reactors. Important aspects of Plutonium-239:

• Fissile Nature: Capable of sustaining a nuclear chain reaction, making it a key material in reactors and nuclear weapons.
• Production: Generated by neutron bombardment of Uranium-238, transitioning it into Plutonium-239.
• Applications: Used in nuclear power to generate electricity and in nuclear weapons programs globally.

Despite its benefits, handling Plutonium-239 requires stringent safety measures due to its radioactive nature and potential use in weapons.
Its role in the energy sector highlights the balance between power generation and safety concerns.