1. Periodic Table -- Organization of Elements
Mendeleev organized the elements based on their increasing atomic mass and their physical properties

5. Properties Determined by the # of e- in the outer energy level
Same number in the outer shell = same group
Example:
Group 1
React explosively with water
Properties

6. Valence electrons
Outer shell electrons

7. Metals Good conductor of heat and electricity Luster (shiny)
Malleable (turn into shapes)

8. Metals (cont)
Ductile: stretched into wire
Solid at room temp
Exception : Hg (Mercury) is liquid at room temp
Left of the zigzag - EXCEPT HYDROGEN

9. Non-metals Right of the zigzag, and hydrogen Lack luster
Do not conduct heat or electricity
Not ductile
Not malleable
Found as solid or gas
Exception: Br (Bromine) on liquid non-metal
Non-metals

10. Non-metals

11. Has properties of both Found along the zigzag Example Po (Polonium)
Metalloids
Has properties of both
Found along the zigzag
Example
Po (Polonium)

12. Reactivity