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Scientific Theories — Reading Comprehension

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MS-PS1-1
MS-PS1-4
MS-PS3-4
SCIENCE AND ENGINEERING PRACTICES
NGSS

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This reading passage for grades 6-8 introduces students to the concept of scientific theories, emphasizing that these are well-tested, widely accepted explanations supported by evidence. Students will learn the differences between a scientific theory and the everyday use of the word 'theory.' The passage provides detailed examples, including atomic theory and kinetic molecular theory, and demonstrates how theories help explain and predict phenomena in the natural world. Real-world applications and connections to broader scientific principles are highlighted, supporting NGSS science standards. The resource includes a glossary, multiple-choice quiz, writing prompts, and graphic organizers to help students explore the mechanisms, evidence, and applications of scientific theories. Audio support is integrated for accessibility, making it ideal for diverse learners and classrooms.

CONTENT PREVIEW

"Colorful abstract representation of molecular structures with 3D spheres and connections." by Google DeepMind / Pexels.

Scientific theories are the backbone of our understanding of the natural world. They offer explanations for phenomena that can be observed, measured, and tested. Unlike a simple guess or an idea that has not been proven, a scientific theory is a well-tested, widely accepted explanation based on a large amount of evidence. Scientists use theories to make sense of patterns in nature, predict future events, and develop new technologies. The difference between the scientific meaning of 'theory' and its everyday use is important: in science, a theory is not a guess, but a powerful explanation supported by facts.

How Scientific Theories Are Built

A scientific theory begins with careful observations of the world. Scientists collect data, ask questions, and design experiments to test their ideas. When repeated experiments and studies produce consistent results, scientists develop explanations to account for these patterns. Over time, if an explanation continues to be supported by new discoveries and is not disproven by evidence, it becomes a scientific theory. For example, atomic theory explains that all matter is made up of tiny particles called atoms. This theory was built over centuries, as scientists observed chemical reactions and measured the properties of substances. Today, atomic theory helps us understand and predict how materials behave, from the rusting of iron to the reactions in our bodies.

Examples: Atomic Theory and Kinetic Molecular Theory

Kinetic molecular theory is another example of a scientific theory. It explains that all matter is made of particles that are in constant motion. This theory helps us understand why gases spread out to fill a container, or why heating a substance usually makes it expand. Both atomic theory and kinetic molecular theory are supported by evidence from experiments, such as measurements of temperature, pressure, and volume. These theories are used in fields ranging from chemistry to engineering, and they help scientists design new materials, fuels, and medicines. Theories can be improved or revised as new evidence appears, but they remain valid as long as they are supported by data.

Scientific Theories in Society and Technology

Scientific theories do more than explain how things work; they also have practical applications. For instance, atomic theory has led to the development of nuclear energy, medical imaging, and new materials like plastics. Kinetic molecular theory is used to design refrigeration systems and predict weather patterns. The strength of a scientific theory comes from its ability to explain a wide range of phenomena and to make accurate predictions. As technology advances, theories may be refined, but the process of building and testing theories is central to science and progress.

Scientific theories are essential for making sense of the world, developing technology, and solving real-world problems. Understanding the difference between a scientific theory and a guess helps us appreciate the power of scientific thinking and the importance of evidence in science.

Interesting Fact: The atomic theory was first proposed over 2,000 years ago by Greek philosopher Democritus, but it took centuries of scientific observation and experimentation to become the well-supported theory we use today!

What is a scientific theory?

A well-tested, widely accepted explanation based on evidence.A random guess without support.An idea that cannot be tested.A simple observation.

What does atomic theory explain?

That all matter is made of atoms.That all matter is made of energy.That all matter is invisible.That all matter is living.

Which of the following is an example of evidence?

Data from repeated experiments.A scientist's guess.A new technology.A random idea.

What does the kinetic molecular theory help explain?

Why gases spread out in a container.Why plants are green.Why metals conduct electricity.Why animals breathe oxygen.

In science, what is the difference between a theory and a guess?

A theory is based on evidence; a guess is not.A guess is always correct; a theory is not.A theory is just an idea.There is no difference.

Which word in the passage means 'facts, measurements, and information collected in studies'?

DataPredictionTechnologyPhenomena