1. Chapter 3, Section 4 Non-Metals and Metalloids Tuesday, November 17, 2009 Pages 98 -- 103

2. Objectives Locate nonmetals and metalloids in the periodic table. Compare the physical and chemical properties of nonmetals with those of metals, and describe the properties of metalloids.

3. Vocabulary Words Nonmetal Diatomic molecule Halogen family Noble gas Metalloid Semiconductor

4. What is a Nonmetal? Nonmetals are the elements that don’t have the properties of metals. Nonmetals are located to the right of the zigzag line in the periodic table.

5. Physical Properties of Nonmetal Many of the nonmetal elements are gases at room temperature. Nonmetal elements have a low boiling point. Nonmetals are dull. Solid nonmetals are brittle, not malleable, and not ductile. Nonmetals have a low density. They are poor conductors of heat and electricity.

6. Chemical Properties of Nonmetals Most nonmetals readily form from compounds with the exception of Group 18 elements. Group 18 elements do not gain, lose, or share electrons. This causes them to not react with other elements.

7. Compounds of Nonmetals Valence electrons move from the metal atoms to the nonmetal atoms when these two types of metals react. Group 17 easily reacts this way. Nonmetals can form compounds with other nonmetals. The atoms will share electrons and bond together to form molecules.

8. Diatomic Molecule Nonmetals forming molecules of two identical atoms are called diatomic molecules. Examples include O 2, N 2, and H 2.

9. The Carbon Family Group 14 is also known as the Carbon Family. Each element in the carbon family has 4 valence electrons.

10. The Nitrogen Family Group 15 is also known as the Nitrogen Family. Each element contains 5 valence electrons.

11. The Oxygen Family Group 16 is also known as the Oxygen Family. Each element contains 6 valence electrons

12. The Halogen Family Group 17 is also known as the Halogen Family. Each element has 7 valence electrons. All Halogen elements are reactive and dangerous to humans. Halogen compounds, however, can be useful.

13. Noble Gases Group 18 elements are also known as Noble Gases. Noble gases do not form compounds with other elements. Atoms of noble gases do not gain, lose, or share their valence electrons.

14. Hydrogen This element sits alone in the upper left corner of the periodic table. Its chemical properties differ from other elements so much that it cannot be grouped into a family.

15. Metalloids Metalloids are between the metals and nonmetals. There are 7 metalloid elements. Metalloids share characteristics of both metals and nonmetals. These elements have a varying ability to conduct electricity (depends on temperature, exposure to light, presence of impurities). Silicon computer chip

16. Homework Workbook 3.4 due 11/19. Vocabulary Quiz 3.4 on 11/19.