Unit 7, Chapter 22
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Unit 7, Chapter 22. Integrated Science. Unit Seven: Changes in Matter. Chapter 22 Chemistry and the Environment. 22.1 Nuclear Reactions 22.2 Carbon Reactions and the Environment. Chapter 22 Learning Goals. Compare and contrast nuclear reactions with chemical reactions.
Unit 7, Chapter 22
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Unit 7, Chapter 22 Integrated Science
Unit Seven: Changes in Matter Chapter 22 Chemistry and the Environment • 22.1 Nuclear Reactions • 22.2 Carbon Reactions and the Environment
Chapter 22 Learning Goals • Compare and contrast nuclear reactions with chemical reactions. • Describe the environmental impact of nuclear reactions. • Research and describe the environmental and economic impact of the end-products of chemical reactions. • Identify how personal choices about products can have an impact on the environment. • Evaluate the impact of scientific research on society and the environment. • Organize data and use it to predict trends.
half-life neutral nuclear reactions nucleons photosynthesis radiation radioactive radioactive isotope stable unstable Chapter 22 Vocabulary Terms • alpha decay • alpha particles • beta decay • beta particles • carbon dating • emissions • fission • fossil fuels • fusion • global warming
22.1 Nuclear Reactions • In the Middle Ages, individuals called alchemists spent a lot of time trying to make gold. • Making an element is possible only if you can achieve a nuclear reaction. • Nuclear reactions involve either combining or splitting the nuclei of atoms.
22.1 Nuclear Reactions • There are two kinds of nuclear reaction: fusion and fission. • The process of combining the nuclei of atoms to make different atoms is called fusion.
22.1 Nuclear Reactions • Breaking up the nucleus of an atom is called fission.
22.1 Nuclear Reactions • Fission and fusion are nuclear reactions. • Protons and neutrons—the two most important subatomic particles in the nucleus—participate in these reactions. • Collectively, the protons and neutrons in the nucleus are called nucleons.
22.1 Radioactivity • Unstable isotopes emit three kinds of radioactive decay: • alpha particles • beta particles • gamma rays • An unstable nucleus is radioactive.
22.1 Using Nuclear Reactions • Radioactive isotopes can be used to detect problems in organ systems. • The age of some fossils can be determined using radioisotopes such as carbon-14. • It is possible to figure out the age of objects made from plants or animals that are between 50,000 and a few thousand years old using carbon dating.
Key Question: How do you simulate nuclear decay? 22.1 Nuclear Reactions *Read text section 22.1 BEFORE Investigation 22.1
22.2 Carbon Reactions in the Environment • We all depend on the carbon reactions performed by plants. • Plants convert the sun’s energy into products we use.
22.2 Carbon Reactions in the Environment • We depend on carbon reactions for transportation. • Cars burn fossil fuels for energy. • Use of fossil fuels affects the environment.
22.2 Carbon Reactions in the Environment • Incomplete combustion means more air pollution. • The catalytic converter, introduced in the 1970s, reduces hydrocarbon and carbon monoxide emissions by converting these molecules to carbon dioxide and water.
Key Question: How do your choices impact the environment? 22.2 Carbon Reactions in the Environment *Read text section 22.2 BEFORE Investigation 22.2