1. Periodic Table

1. Periodic Table

1. 2. Dimitri Mendeleev

   • developed the periodic table
   • 1860's

2. 3. Atomic Symbol

   • letter representation of elements
   • come from latin names

3. arrangment of the elements

4. 4. Period

   • rows of the elements
   • represents one "shell" of electrons

5. 5. Elements "family"

   • column of similar elements in the periodic table
   • 6. Elements Group
     • have identical physical and chemical properties
     • 7. Non-metals
       • poor conductors
       • only 20 elements
     • 8.Metals
       • make the vast majority of elements
       • are good conductors
       • 15.Malleable
         • does not break easily
         • can be hammered into sheets
       • 16.Ductile
         • part of the metal "family"
         • element that can be pulled into wires when heated
     • 9.Metalloids
       • have some properties of metals and non-metals
       • the smallest category of elements

6. 10. Average Atomic Mass

   • sum of the element's isotopes masses
   • each isotopes multiplied by its natural abundance

7. 11. Valence Electrons

   • electrons in element's outer-most electron cloud
   • determine element's reaction to other elements

8. 12. Reactive Elements

   • the tendency of a substance to undergo chemical reaction,
   • fluorine is the most reactive element

9. 13. Non-reactive Elements

   • Helium is a Noble Gas
   • farthest right column, "Noble Gas"

10. 14.Chemists

    • an expert in chemistry; a person engaged in chemical research or experiments.
    • Marie Curie was a chemist