2. Periodic Table A General Overview

3. The Periodic Law Dimitri Mendeleev (1869/1871) was the first scientist to publish an organized periodic table of the known elements. He was taking a chemistry course in Russia and tried to find a way to organize the periodic table.

4. The Periodic Law Mendeleev even went out on a limb and predicted the properties of 2 at the time undiscovered elements. He was very accurate in his predictions, which led the world to accept his ideas about periodicity and a logical periodic table.

5. The Periodic Law Mendeleev understood the ‘ Periodic Law ’ which states: When arranged by increasing atomic number, the chemical elements display a regular and repeating pattern of chemical and physical properties.

6. The Periodic Law Groups/Families Elements with similar chemical properties and behavior appear Vertical columns in periodic table Periods horizontal rows on periodic table Fairly predictable change in chemical/physical properties. Lanthanide/Actinide series Found under the main table Actually fit between atomic numbers 57 and 89

7. Metals, Nonmetals, Metalloids

8. There is a zig-zag or staircase line that divides the table. Metals are on the left of the line, in blue. Nonmetals are on the right of the line, in orange.

9. Metals, Nonmetals, Metalloids Elements that border the stair case, shown in purple are the metalloids or semi- metals. There is one important exception. Aluminum is more metallic than not.

10. Metals, Nonmetals, Metalloids How can you identify a metal? What are its properties? What about the less common nonmetals? What are their properties? And what the heck is a metalloid?

11. Metals Metals are shiny, malleable, ductile, and are good conductors of heat and electricity. They are mostly solids at room temp. Exception: Mercury

12. Nonmetals Nonmetals are the opposite. No color, no shine They are dull, brittle, nonconductors (insulators). Gases at room temperature Some are solid at room temperature (C, P, Se, S, I)

13. Metalloids/Semi-Metals Metalloids, aka semi-metals are just that. They have characteristics of both metals and nonmetals. They are shiny (like metals) but brittle. Solids at room temperature And they are semiconductors. “on the fence, middle of the road” B, Si, As, Te, At, Ge, Sb, Po

14. Noble Gases Group 18 Do NOT react with other elements Unusual elements Gases at room temperature Ne, Ar, Kr, Xe, Rn, He

15. Classwork: Metal Identity Identify each element as a nonmetal, metal, or metalloid 1) Na6) Cl 2) P7) Mg 3) Se8) Al 4) Ge9) Sb 5) N10) Si

16. Homework Read pp. 43-49