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Nuclear Fusion — Reading Comprehension

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MS-PS3-4

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This middle school science passage introduces students to the concept of nuclear fusion, the process that powers the Sun and stars. Aligned with NGSS standards MS-PS1-1 and MS-PS3-4, the passage explains how fusion combines light atomic nuclei, like hydrogen, into heavier nuclei, like helium, releasing vast amounts of energy. Students will learn about the mechanisms of fusion, why it requires extreme temperature and pressure, and how it differs from nuclear fission, which is currently used in nuclear power plants. The reading also explores the difficulties of achieving nuclear fusion on Earth and its potential as a future clean energy source that produces less radioactive waste than fission. Activities include a reading comprehension quiz, writing prompts, and graphic organizers to deepen understanding. The passage is available in both English and Spanish, with differentiated versions for various reading levels. This resource also includes audio integration for enhanced accessibility and is ideal for grades 6-8 science classrooms.

CONTENT PREVIEW

Two nuclei fuse, releasing energy and forming new particles. — Nuclear fusion: energy released as atomic nuclei combine.

Nuclear fusion is the process that allows our Sun and other stars to shine brilliantly for billions of years. This powerful reaction occurs when two or more light atomic nuclei join together to form a heavier nucleus, releasing tremendous amounts of energy in the process. Nuclear fusion is not only the source of solar energy that warms Earth, but it also represents a potential solution for our future energy needs.

The Mechanism of Fusion

Fusion happens when light atomic nuclei, such as hydrogen, are forced close enough together that the strong nuclear force binds them into a single, heavier nucleus. This process requires extremely high temperatures (over 15 million degrees Celsius in the Sun) and immense pressure to overcome the natural repulsion between positively charged nuclei. In the Sun, hydrogen nuclei fuse to form helium, releasing energy according to Einstein’s equation, E=mc², which shows that a small amount of lost mass becomes a large amount of energy. More than 99% of the Sun’s energy comes from fusion reactions.

Fusion on Earth and Its Challenges

Scientists have long seen fusion as a potential clean energy source, since it uses abundant fuels like hydrogen and produces much less radioactive waste than nuclear fission. Fission, used in today’s nuclear power plants, splits heavy nuclei like uranium to release energy, but it generates hazardous waste and relies on rare elements. Fusion, by contrast, uses lighter elements and offers the promise of nearly limitless, safe energy. However, reproducing the necessary temperatures and pressures for fusion on Earth is extremely difficult. Devices called tokamaks and lasers are being developed to contain and heat fuel for fusion, but so far, no reactor has produced more energy than it consumes.

Fusion vs. Fission: A Comparison

Fusion and fission both release energy from atomic nuclei, but they do so in opposite ways. Fusion combines light nuclei, usually isotopes of hydrogen, while fission splits heavy nuclei like uranium. Fusion produces less long-lived radioactive waste and does not create the risk of a nuclear meltdown. However, fission is easier to achieve with current technology, which is why it is used in all nuclear power plants today. If scientists can solve the technical problems of fusion, it could become a key part of clean energy systems for the planet’s future.

Fusion demonstrates how understanding the interactions of matter and energy can lead to transformative technologies. The pursuit of fusion energy highlights the need for scientific research and innovation in addressing global challenges.

Interesting Fact:
Just one gram of fusion fuel can release as much energy as burning about eight tons of coal!

What is nuclear fusion?

The process where light atomic nuclei combine to form a heavier nucleus, releasing energy.The splitting of heavy nuclei into lighter nuclei.The process that creates radioactive waste.A reaction that only occurs on Earth.

What powers the Sun and most stars?

Nuclear fissionChemical combustionNuclear fusionWind energy

Which element is most commonly used as fuel in fusion reactions in the Sun?

UraniumHeliumHydrogenCarbon

Why is nuclear fusion considered a clean energy source?

It uses rare and expensive fuels.It produces less radioactive waste than fission.It is easier to achieve than fission.It creates more pollution than coal plants.

What is a tokamak?

A special machine designed to contain and heat fuel for nuclear fusion.A type of radioactive waste.A heavy atomic nucleus.A chemical used in fission reactors.

What does the term 'strong nuclear force' mean in the passage?

The force that pushes atoms apart.The force that holds nuclei together.A type of radioactive waste.The heat from the Sun.

Why is it difficult to achieve nuclear fusion on Earth?

It requires extremely high temperatures and pressures.It uses rare elements.It creates too much radioactive waste.It is illegal in most countries.

Which statement best describes the difference between fusion and fission?

Fusion splits heavy nuclei, while fission combines light nuclei.Fusion produces more radioactive waste than fission.Fusion combines light nuclei, while fission splits heavy nuclei.They are the same process.

True or False: Nuclear fusion currently produces more energy than it uses in Earth’s reactors.

TrueFalse

True or False: Fusion reactions in the Sun convert hydrogen into helium.

TrueFalse