Atomic Structure and the Periodic Table CHAPTER NEW CHAPTER Atomic Structure and the Periodic Table the BIG idea A substance’s atomic structure determines its physical and chemical properties. 5.1 Atoms are the smallest form of elements. 5.2 Elements make up the periodic table. 5.3 The periodic table is a map of the elements. CHAPTER OUTLINE CHAPTER RESOURCES

Atoms are the smallest form of elements. 5.1 Atoms are the smallest form of elements. • All matter is made of the atoms of approximately 100 elements. proton • Atoms are made of protons, neutrons, and electrons. neutron neutron electron cloud nucleus proton nucleus electron atomic number atomic mass number isotope ion CHAPTER RESOURCES SIMULATION Build a model of an atom. CLASSZONE.COM SECTION OUTLINE

Atoms are the smallest form of elements. 5.1 Atoms are the smallest form of elements. • All matter is made of the atoms of approximately 100 elements. proton • Atoms are made of protons, neutrons, and electrons. neutron • Different elements are made of different atoms. nucleus • Atoms form ions by gaining or losing electrons. electron 11 electrons (11-) 10 electrons (10-) Sodium Atom (Na) Loses 1 electron Sodium Ion (Na ) + atomic number atomic mass number isotope ion CHAPTER RESOURCES SECTION OUTLINE

Elements make up the periodic table. 5.2 Elements make up the periodic table. • Elements can be organized by similarities. • The periodic table organizes the atoms of the elements by properties and atomic number. atomic mass periodic table • Groups of elements have similar properties. group period F Cl Br I At Group 17 CHAPTER RESOURCES SECTION OUTLINE

Elements make up the periodic table. 5.2 Elements make up the periodic table. • Elements can be organized by similarities. • The periodic table organizes the atoms of the elements by properties and atomic number. atomic mass periodic table • Groups of elements have similar properties. group • Elements in a period have varying properties. period Mg Na Al Si P S Cl Ar Period 3 CHAPTER RESOURCES SECTION OUTLINE

The periodic table is a map of the elements. 5.3 The periodic table is a map of the elements. • The periodic table has distinct regions. reactive metal metalloid nonmetal metal nonmetal metalloid radioactivity half-life CHAPTER RESOURCES SECTION OUTLINE

The periodic table is a map of the elements. 5.3 The periodic table is a map of the elements. • The periodic table has distinct regions. • Most elements are metals. reactive • Nonmetals and metalloids have a wide range of properties. metal • Some atoms can change their identity through radioactive decay. nonmetal metalloid Original Isotope Remaining (%) Radioactive Decay 100 50 25 12.5 1 2 3 4 Number of half-lives = original element = new element radioactivity half-life VISUALIZATION Watch how a radioactive element decays over time. CLASSZONE.COM CHAPTER RESOURCES SECTION OUTLINE

5.1 Atoms are the smallest form of elements. I. Atoms are the smallest form of elements. proton A. All matter is made of atoms. neutron 1. Types of Atoms in Earth’s Crust and Living Things nucleus electron 2. Names and Symbols of Elements B. Each element is made of a different atom. atomic number 1. The Structure of an Atom atomic mass number 2. Atomic Numbers isotope 3. Atomic Mass Numbers ion C. Atoms form ions. CHAPTER RESOURCES 1. Formation of Positive Ions 2. Formation of Negative Ions KEY CONCEPT SUMMARY

Elements make up the periodic table. 5.2 Elements make up the periodic table. II. Elements make up the periodic table. atomic mass A. Elements can be organized by similarities. periodic table 1. Mendeleev’s Periodic Table group 2. Predicting New Elements period B. The periodic table organizes the atoms of the elements by properties and atomic number. 1. Reading the Periodic Table 2. Groups and Periods 3. Trends in the Periodic Table CHAPTER RESOURCES KEY CONCEPT SUMMARY

The periodic table is a map of the elements. 5.3 The periodic table is a map of the elements. III. The periodic table is a map of the elements. reactive A. The periodic table has distinct regions. metal B. Most elements are metals. 1. Reactive Metals nonmetal 2. Transition Metals metalloid 3. Rare Earth Elements radioactivity C. Nonmetals and metalloids have a wide range of properties. half-life 1. Halogens 2. Noble Gases 3. Metalloids CHAPTER RESOURCES D. Some atoms can change their identity. 1. Uses of Radioactivity in Medicine KEY CONCEPT SUMMARY 2. Radioactive Decay

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