Problem 48 - Chemistry and Chemical Reactivity

Question

Tritium, \(\frac{3}{1} \mathbf{H},\) is one of the nuclei used in fusion reactions. This isotope is radioactive, with a half-life of 12.3 years. Like carbon-14, tritium is formed in the upper atmosphere from cosmic radiation, and it is found in trace amounts on earth. To obtain the amounts required for a fusion reaction, however, it must be made via a nuclear reaction. The reaction of \(1\) i with a neutron produces tritium and an \(\alpha\) particle. Write an equation for this nuclear reaction.

Step-by-Step Solution

Answer

The equation is \( ^2_1H + ^1_0n \rightarrow ^3_1H + \alpha \).

Step 1: Understanding the reaction components

The reaction involves an isotope, denoted as 1 i, reacting with a neutron to produce tritium and an alpha particle. We need to identify the reactants and products to write the equation. Tritium is symbolized as \( ^3_1H \), a neutron is symbolized as \( ^1_0n \), and an alpha particle is symbolized as \( ^4_2He \). The isotope '1 i' is likely a reference to heavy water, often written as \( ^2_1H \), which is deuterium.

Step 2: Setting up the reaction equation

According to the problem, deuterium (\( ^2_1H \)) reacts with a neutron (\( ^1_0n \)) to produce tritium (\( ^3_1H \)) and an alpha particle (\( ^4_2He \)). This sets up the reactants and products for the reaction equation: \( ^2_1H + ^1_0n \rightarrow ^3_1H + ^4_2He \).

Key Concepts

Fusion Reactions

Fusion reactions are fascinating processes where two light atomic nuclei join to form a heavier nucleus. This is the same process that powers the sun, providing it with immense energy. For a fusion reaction to occur, the involved nuclei need to overcome their repulsive forces, often with the assistance of extremely high temperatures. This is why fusion occurs naturally in stars, thanks to their intense heat.
Fusion is seen as a potential energy source here on Earth because it generates a huge amount of energy compared to nuclear fission, without the dangerous long-lived radioactive waste. In the exercise provided, tritium is used as one of the nuclei in the fusion reaction. To achieve this reaction, tritium often pairs with another hydrogen isotope, such as deuterium.

• The reaction between deuterium and tritium is especially noteworthy due to its high energy output.
• These reactions are efficient, releasing energy mainly in the form of kinetic energy of the products.
• The generated energy could eventually be harvested to produce electricity on a large scale.

Radioactive Isotopes

Radioactive isotopes are versions of elements with unstable nuclei. These isotopes emit radiation as they break down to become more stable forms. Tritium, which is used in numerous scientific applications, is a radioactive isotope of hydrogen.
Its radioactive nature means it can spontaneously decay and transform into a different element. For tritium, the half-life is 12.3 years. This means that over 12.3 years, half of any amount of tritium would have decayed into helium-3 through radioactive decay.

• Radioactive isotopes find extensive use in medical imaging and treatment.
• They are also used in tracing and dating archaeological artifacts.
• Housing and adjusting isotopes carefully is crucial, given their potential environmental impact.

Understanding isotopes like tritium is key when studying nuclear reactions. Their unique properties help scientists utilize them effectively while also ensuring safety.

Nuclear Equations

Nuclear equations represent reactions occurring in atomic nuclei. These equations are pivotal in understanding both natural and artificial nuclear processes. Unlike chemical equations that involve electrons, nuclear equations focus on the changes within a nucleus, including neutron, proton, and equivalent nuclear components.
In writing these equations, the conservation of mass and charge must be respected. That means the sum of mass numbers (protons and neutrons) and the sum of atomic numbers (charges) must match on both sides of the equation.

• In the exercise problem, the nuclear reaction equation was: \( ^2_1H + ^1_0n \rightarrow ^3_1H + ^4_2He \).
• This shows how deuterium and a neutron combine to produce tritium and an alpha particle.
• Such equations help scientists track nuclear transformations and predict resulting elements and particles.

Practicing the writing of nuclear equations increases one’s understanding of the principles of nuclear chemistry. It's essential for predicting nuclear reaction outcomes accurately.

Cosmic Radiation

Cosmic radiation consists of energetic particles originating from outer space. When these particles reach Earth's atmosphere, they collide with atoms, causing nuclear reactions and leading to the production of new isotopes, such as carbon-14 and tritium, mentioned in the exercise.
These high-energy radiation particles are primarily protons but also include some heavier nuclei. They travel through the cosmos and reach Earth's atmosphere, generating showers of secondary particles upon interaction.

• These interactions are a natural source of some radioisotopes found on Earth.
• Cosmic radiation contributes to background radiation levels, which are monitored and studied for impacts on life and technology.
• Scientists study cosmic radiation to understand its origin, behavior, and impact on the solar system and beyond.

Despite being mostly harmless due to Earth's protective atmosphere, cosmic radiation continues to intrigue scientists who explore its extensive implications.