1. Organizing the Elements
The Periodic Table
Organizing the Elements

2. Your Periodic Table

3. The Periodic Table of Elements

4. Mendeleev’s Periodic Table
Elements were arranged horizontally by increasing atomic mass. Elements were grouped vertically according to similar characteristics

5. Mendeleev’s Breakthrough
An element’s properties can be predicted based on its location in the periodic table.
Mendeleev was able to predict the existence of 5 yet-to-be- discovered elements
Prediction
Discovered
Ekaaluminium (1871):
atomic mass = 68
density = 6.0
Gallium (1875):
atomic mass = 69.72
density = 5.904
Ekasilicon (1871):
atomic mass = 72
density = 5.5
color = grey
Germanium (1886):
atomic mass = 72.61
density = 5.35

6. The Modern Periodic Table
Elements are now arranged by increasing atomic number (number of p+).
Instead of atomic mass (# of p+ and n0)
Elements in vertical columns share similar characteristics.
This creates a repeating pattern of characteristics as you move across each row.
The word “periodic” means regular, repeated pattern.

7. 4 Important Facts about the Elements
Inside the Boxes
4 Important Facts about the Elements C
Carbon
Element Name 6 C
Carbon
12.011
Element Symbol
Atomic Number
Atomic Mass
(“atomic weight”)

8. Inside the Boxes 4 Important Facts about the Elements
Element Name – Duh…
Element Symbol – 1, 2, or 3 letters that represent the name of the element
The symbol may or may not be similar to the English name of the element
Many derive from the Latin name of the element
Atomic Number – The number of protons (p+)found in the nucleus
Atomic Mass – The average number of protons (p+) and neutrons (n0) in the nucleus
a.m.u. (atomic mass unit) = mass of 1 proton or 1 neutron

9. Organization GROUPS 18 vertical columns
Each group is numbered (# on top of columns)
Also called, “families” (i.e. – the lithium family)
Elements in a family share similar characteristics
Valence Electrons (groups 1-2, 13-18)

10. Interesting Element “Families”
Group 1 (Alkali Metals) are all metals that react violently with water.
Group 11 (Copper Family) are all metals that react with water slowly or not at all.
Group 18 (Noble Gases) rarely react at all!

11. Organization PERIODS 7 horizontal rows
Each period is numbered (# on left of rows)
La’s and Ac’s are part of period 6 and 7
Arranged based on the configuration of electrons (implications in chemical bonding)
Periods display a repeating pattern of characteristics

12. # of p+ increases left to right
Patterns in the Table
# of p+ increases left to right

13. atomic mass increases left to right
Patterns in the Table
atomic mass increases left to right

14. elements in groups share #’s of valence e-1
elements in groups share #’s of valence e- 8 2 3 4 5 6 7

15. similar characteristics

16. increasing density down the columns

17. classifications Alkaline Earth Metals Noble Gasses Alkali Metals
Halogens
Non-Metals
Metalloids
Transition Metals
Lanthanides
Actinides

18. G
standard state
Gasses L
Solids L