Topic : Chemistry Aim : How are elements classified in the Periodic Table?

1. Topic: Chemistry Aim: How are elements classified in the Periodic Table? Do Now: An atom has atomic number of 15. How many protons does it have?

2. Periodic Table of Elements • System of classifying or all of the known elements and to predict the properties of elements

3. How are elements arranged? • In order of increasing atomic number

4. Element Key

7. Groups or Families • Columns • Elements have similar BUT NOT identical properties

8. Hydrogen • Element does not match the properties of any other group so it stands alone • Placed above group 1  not part of group 1 • Very reactive, colorless, ordorless gas at room temp

9. Ex: Family/Group 1: Alkali Metals • soft, white, shiny metals • highly reactive

10. 2:ALKALINE EARTH METALS Group 2 • White and malleable • Reactive, but less than Alkali metals

11. 3-11:TRANSITION METALS Range of reactivity & wide range of properties Most of the elements on PT

12. Periods • Rows (7) • Elements not alike in properties • Left to right  atomic # increases

13. 4 main categories of elements • Metals, Nonmetals, Metalloids, Noble Gases

14. 1. Metals • 88 elements to left of zigzag line

16. Physical Properties of Metals • Luster (shininess) • Ductile (can be pulled into wires) • Malleable (can be hammered into sheets) • Good conductors (allow heat and electricity to move through easily)

17. 2. Nonmetals • To right of zigzag line

18. Physical Properties of Nonmetals • No luster (dull) • Brittle (break) • Poor conductors of heat and electricity

19. Sulfur

20. 2. Metalloids • Have properties of both metals and nonmetals

22. Noble Gases • Last group of nonmetals • He, Ne, Ar, Kr, Xe, Rn • INERT gases • Non-reactive

23. Noble gases glow brightly when electricity is passed through them, and so are used as advertising signs: neon tubes glow red, xenon blue, and krypton bluish-white; argon tubes glow pale red at low pressures, blue at high pressures.

24. Review: • Explain how the periodic table of elements is arranged. • Elements at the left of the periodic table are known as • Elements at the right of the periodic table are known as • Explain some of the properties of metals. • Explain some of the properties of nonmetals. • Explain some properties of noble gases.

25. 3-11:TRANSITION METALS Good conductors of heat and electricity. Some are used for jewelry. Can bond with many elements in a variety of shapes.

26. 1st element  extremely active solid • Last element  inactive gas