1. Periodic Table: Representation & Organization
4-Ch 1

2. The Periodic Classification of the Elements  The Periodic Table
Periodic Classification: A way to group the elements according to certain properties
Periodic Table of Elements: a visual presentation of the elements in groups according to their physical and chemical properties

3. Review: Physical vs Chemical Properties
Physical Property: A property that can be observed or measured without changing the make-up of the matter of the object (ex: colour, odor, texture, density, melting point, boiling point)
Chemical Property: Cannot be determined by simply viewing or touching the object; only becomes evident during a chemical reaction (ex: reactivity with other chemicals, flammability, heat of combustion)

4. How the Periodic Table is Divided/Organized
Each element has its own box/square
For each element:
Symbol of the Element: This is universal (same for all languages)
Atomic Number: always located at the top
Atomic Mass: always located at the bottom
Name of the Element: Written in the language of the document

5. First Major Division: Metals, Non-Metals & Metalloids
All the elements can be placed into these three categories
The “staircase” helps locate and identify the categories

6. Metals Location: To the LEFT of the staircase Properties:
Conduct heat and electricity well
Ductile (can stretch)
Malleable (can bend)
Usually shiny (luster)
Soft
Very reactive with water & acids
High melting point
Solid at room temperature EXCEPT for Mercury (liquid)

8. Non-Metals Location: To the RIGHT of the staircase EXCEPT for Hydrogen
Properties:
Poor conductors of heat and electricity
Many are gases at room temperature
No lustre
Not malleable, ductile or soft

10. Metalloids Location: Found along the “staircase” Properties:
Only 7 in total (Boron, Silicon, Germanium, Arsenic, Antimony, Tellerium, Astatine)
Have some properties of metals AND some of non-metals
Some are very good conductors, others are very poor – used as semiconductors in circuits and lasers

12. Groups of the Periodic Table
All the elements found in one COLUMN (going up and down) belong to a GROUP
All elements in a group have:
Similar chemical properties
The same number of valence electrons
Groups are labeled using Roman numerals (1 = I, 2 = II) and either A or B
“A” = main elements (biggest columns)
“B” = transition elements (short columns)
Roman numeral = number of valence electrons

13. Alkali Metals
Location: The first column on the left of the periodic table (except Hydrogen)
Properties:
Soft
HIGHLY reactive metals

14. Alkaline Earth Metals
Location: The second column on the periodic table
Properties:
Highly malleable (soft)
Reactive
Burn easily in the presence of heat

15. Halogens Location: The second-last column on the periodic table
Properties:
Non-metals
React easily to form compound
Commonly form salts when combined with metals

16. Noble Gases (Inert Gases)
Location: The final column of the periodic table (on the right)
Properties:
Very stable, do not react well
Commonly found in nature
Bright light is produced when electricity is passed through

17. The Periods of the Periodic Table
Elements found in each row (going across) have the same number of shells around the nucleus
The period number corresponds to the number of electron shells