1. Understanding the Periodic Table of Elements

3. Mendeleev: Discovered a set of patterns that helped him organize
Repeating Order Metals, Metalloids, Non-Metals
*Except for Hydrogen*
Elements are made of only One kind of Atom
Symbols have either one or two letters
The first letter of each symbol is a capital letter
The second letter is a lowercase letter

4. What is the Periodic Table?
a table of the chemical elements in which the elements are arranged by order of increasing Atomic Number, which is also the # of protons
Horizontal Rows – Periods (7)
Vertical Columns – Groups (18) can also be called “Families”
An element’s properties can be predicted from its location in the periodic table

5. Groups Periods Elements in the same Group have similar properties
Elements in the same Periods have the same # of orbitals

6. Reading the Periodic Table

7. Atomic Number = # of protons = # of electrons Atomic Mass = # of protons + # of neutrons 26 54 25 56