1. The Periodic Table
An Introduction

2. Johann Dobereiner
1829
Organized the elements into triads, or groups of three based on properties.

3. John Newlands
1863
Organized the elements by octaves, or groups of eight, because some properties repeated every 8th element.

4. Dmitri Mendeleev
1869
Published a table of the elements arranged by increasing atomic mass.
Called the “Father of the Periodic Table”
Left gaps on his periodic table for elements that had not yet been discovered.

5. Henry Moseley
1913
Rearranged the periodic table in order of increasing atomic number.
Called the “Father of the Modern Periodic Table”

6. And Now We Have This Beauty!

7. I Bet There are Interesting Things About the Periodic Table I have to Memorize!
Columns (up and down)
= Groups or Families
Rows (across)
= Periods
That was easy….what’s next?

8. Metals, Nonmetals, and MetalloidsB Si Ge As Sb Te At

9. Properties of… Metals Nonmetals Metalloids Solid (except Hg) Shiny
Conduct heat &
electricity
Ductile: can be stretched into wire
Malleable: can be hammered into sheets
Lose e- easily
Opposite of metals.
*Includes Hydrogen
Brittle (break easily)
Poor conductors of heat & electricity
Tend to gain electrons in chemical reactions
Properties a mix of metals and nonmetals.
Partially conduct electricity.

10. How About Some of the Other Families?
Alkali Metals: far left column
All soft metals that react violently with water to make Hydrogen gas.

11. Alkaline Earth Metals: group 2
All are shiny, silvery-white, and somewhat reactive.

12. Transition Metals: d block
Very hard with high melting and boiling points (except Hg, of course)

13. Halogens: group 7
7 valence electrons
Highly reactive, especially with alkali metals and alkaline earth metals

14. Noble Gases: far right column
Full outer shells = nonreactive
All gases at room temperature