0072_sx09_K_te_Ch03.fm Page 98 Sunday, January 13, 2008 1:38 PM
Objectives After this lesson, students will be able to Reading Preview K.3.4.1 Describe the properties of Key Concepts What Are the Properties of Charcoal? nonmetals. • What are the properties of 1. Break off a piece of charcoal and roll it between your ﬁngers. K.3.4.2 Tell how metalloids are useful. nonmetals? Record your observations. • How are the metalloids useful? 2. Rub the charcoal on a piece of paper. Describe what happens. 3. Strike the charcoal sharply with the blunt end of a fork. Target Reading Skill Key Terms Describe what happens. • nonmetal Using Prior Knowledge Explain that using 4. When you are ﬁnished with your investigation, return the • diatomic molecule • halogen prior knowledge helps students connect charcoal to your teacher and wash your hands. • noble gas • metalloid what they already know to what they are • semiconductor Think It Over about to read. Classifying Charcoal is a form of the element carbon. Would Target Reading Skill you classify carbon as a metal or a nonmetal? Use your Answers observations from this activity to explain your answer. Sample answers: Using Prior Knowledge Before you read, write what you know What You Know about the properties of nonmetals 1. Nonmetals are not shiny. and metalloids in a graphic Life on Earth depends on nonmetals. All organisms are made 2. organizer like the one below. As from compounds of carbon. The air you and other living things Nonmetals are not magnetic. you read, write what you learn. What You Learned breathe contains mostly nitrogen and oxygen. Water, a key compound in living cells, consists of hydrogen and oxygen. Yet, 1. Nonmetals are dull and brittle. What You Know while many compounds made with nonmetals are essential to 2. Metalloids have characteristics of metals 1. Nonmetals are not shiny. life, some nonmetals themselves are poisonous and highly and nonmetals. 2. reactive. Still others are completely unreactive. Compared to Teaching Resources metals, nonmetals have a much wider variety of properties. However, nonmetals do have several properties in common. • Transparency K28 What You Learned 1. 2. Preteach Build Background Knowledge L2 Experience With Chlorine Ask: What do you know about chlorine? (Sample answer: Chemical used in swimming pools, part of bleach) Encourage students to These bears, the grass build on their experiences with chlorine in behind them, and all life on Earth is based on swimming pools and share their carbon, a nonmetal. observations. Point out the position of chlorine in the periodic table. Invite students to share any knowledge they may have about elements near chlorine.
students that the charcoal has been mixed with clay to keep its shape. Skills Focus Classifying L1 Expected Outcome The charcoal breaks Materials activated charcoal, paper, fork easily, rubs off on ﬁngers and paper, and Time 5 minutes shatters when hit with a fork. Tips Activated charcoal is available where Think It Over Sample answer: Carbon aquarium supplies are sold. You may is brittle, dull, not malleable, and not substitute charcoal briquettes, but tell lustrous. Carbon is not a metal. 0072_sx09_K_te_Ch03.fm Page 99 Sunday, January 13, 2008 1:38 PM
FIGURE 20 Instruct Physical Properties of Nonmetals Nonmetals have properties Properties of that are the opposite of metals. Comparing and Contrasting Nonmetals Contrast the properties of these nonmetals with those of metals. Teach Key Concepts L2 Contrasting Nonmetals and Metals