1. Periodic Table

2. Mendeleev – Father of P.T.
- Arranged elements by characteristics
- Could predict properties of missing elements
- Put alike elements in columns
- Columns – groups or families (18 of them)
Rows – periods (because they repeat) (7)
Find the elements
Group 5
Period 4
Group 15
Period 5 V Sb

3. Group Names Group 1 – alkali metals
* Soft, reactive, 1+ charge as an ion
Group 2 – alkaline earth metals
* Harder, less reactive, 2+ charge as an ion
Groups 3-12 are the Transition metals
* All metals, vary in charge
Group 17 – halogens
* Reactive, nonmetals, diatomic, 1- charge as an ion
Group 18 – noble gas
* Unreactive, all gases

4. metals Make up most of the elements on the P.T.
* Everything left of red zigzag line
Properties of metals
Metallic luster (shiny)
Good conductors of heat/electricity
Ductile/malleable

5. nonmetals Located to right of red zigzag line
Properties of nonmetals (opposite)
Dull
Bad conductors
Brittle

6. metalloids Located on either side of the red zigzag line
Have properties of both:
Shiny but brittle

7. Trends in P.T. Atomic radius: Increases as you go down a group. Why?
Adding more energy levels (rings)
Decreases as you go from left to right. Why?
More protons in nucleus to pull electrons closer.
Symbol colors
Black – solids Blue – liquids Red - gases

8. Ions
When an atom either loses or gains electron(s). Number of electrons lost or gained = charge Cation – loses elcetron(s) - becomes positive Anion – gains electron(s) - becomes negative