The Periodic Table

1. The Periodic Table

2. Assignment • Read • Chapter 1, section 6 • Chapter 3, section 4 • Chapter 3, section 5

3. The Periodic Table • Periodic means occurring or appearing at regular intervals • The Periodic table is designed so that elements with similar characteristics occur or appear at regular intervals

4. The Periodic Table • The table can be divided in many ways • Method 1 • Metals (brown) • Nonmetal (purple) • Metalloids or Semi-metals (green)

5. The Periodic Table • Metals • Most are solid at room temperature (except mercury, Hg) • Usually are shiny solids when freshly cut • Good conductors of heat and electricity • Malleable (meaning can be flattened into a sheet) • Ductile (meaning can be drawn into a wire) • Most have high melting points and boiling points

6. The Periodic Table • Nonmetals • 11 are gases, 5 are brittle solids, and 1 is a liquid at room temperature • Poor conductors of heat and electricity • Most have low melting points and boiling points • Metalloids or Semi-metals • The seven elements that separate the metals and nonmetals • The metalloids tend to have properties of both metals and nonmetals • Ex: Silicon • Metal-like in that it is a shiny solid • Nonmetal-like in that it is a brittle solid • Conductivity lies between that of a metal and non-metal

7. The Periodic Table • Method 3 • Group • Period

8. The Periodic Table • Groups • Indicated by the number at the top of each column • All elements within a group have similar characteristics or properties

9. The Periodic Table • Group 1 – Alkali metals • Soft, shiny metals • Low melting points compared to other metals • Most reactive of the metals that are not radioactive • When added to water they form a highly alkaline (basic) solution – hence the name alkali metals

10. The Periodic Table • Group 2 – Alkaline Earth Metals • Shiny solids • Less reactive than the Alkali metals • Higher melting points than the Alkali metals

11. The Periodic Table • Group 17 – Halogens • All are gases except Bromine • Colorful, corrosive nonmetals • Most reactive of all the nonmetals • The group name halogen comes from the greek word hals, meaning salt, because the halogens are only found in nature in combination with other elements typically forming a salt.

12. The Periodic Table • Group 18 – Noble Gases • Named noble because they lack reactivity.

13. The Periodic Table • Period • Indicated by the number to the left of the row in which the element resides • We will discuss the importance to the period # in chapter 3.

14. The Periodic Table • Method 2 • Main Group elements (yellow) • Transition Metal elements (orange) • Inner Transition Metal elements (blue) • Are not given group #’s. • To determine which period they are members of look at the elemental numbers (atomic #) given at the top of each box. (Expanded version on next slide) • Elements 58-71 are called the Lanthanide series because they follow element #57, Lanthanum • Elements 90-103 are called the Actinide series because they follow element #89, Actinium • The divisions in method 2 will be discussed at length in Chapter 3

15. The Periodic Table