1. How is it organized? You can see it several ways…
The Periodic Table
How is it organized?
You can see it several ways…

2. Metals/ Semi Metals/ Nonmetals
These are the 3 basic categories of elements on the periodic table

3. Elements are arranged:
Vertically into “Groups”
Horizontally Into “Periods”

4. WHY?

5. If you looked at one atom of every element in a group (column) you would see…

6. Each atom has the same number of electrons in its outermost shell.
An example…

7. The group 2 atoms all have 2 electrons in their outer shells
Be (Beryllium)
Atom
Mg (Magnesium) Atom

8. Importance of outer electrons
The number of outer or “valence” electrons in an atom affects the way an atom bonds.
The way an atom bonds determines many properties of the element.
This is why elements within a group usually have similar properties

9. The number of Valence Electrons is fairly easy to find based on what Group (column) the atom is in

10. If you looked at an atom from each element in a period (row)
you would see…

11. Each atom has the same number of electron holding shells (or orbitals)(rings is another term too).
An example…

12. The period 4 atoms each have 4 shells containing electrons
K (Potassium)
Atom
Fe (Iron) Atom
Kr (Krypton)
4th Shell

13. Each group has distinct properties
The periodic table is divided into several groups based on the properties of different atoms.
This is what we will do projects on when we return from break

14. Metals On the left side and middle of the periodic table.
Malleable, shiny, solid at room temp, high melting pt., conduct heat and electricity.

15. Nonmetals On the right side of the p. t. Many are gases at room temp
Solids tend to be brittle, poor conductors, dull appearance

16. Metalloids Along the zigzag (staircase) Properties are in-between
Vary depending on temperature

17. Alkali Metals Softer metals
Reactivity increases as you go down the group
1 valence electron
Can explode with water
Only found in nature in compounds (bonded to something else)
Ex: salt contains sodium (NaCl)
4th period got here

18. Alkaline Earth Metals Still very reactive
Also only found in compounds in nature
2 valence electrons
Ex: calcium in cement and teeth
Ex: magnesium important in photosynthesis (plants getting food from sun)
Got here with 2nd period

19. Transitional Metals Shiny, conductive, malleable, high melting pt.
Ex: iron, cobalt, nickel, zinc, gold, titanium

20. Boron Family Boron is a metalloid, but others are metals
Contains most abundant metal in Earth’s crust, Aluminum.
Soft, weak metals, can be made strong if combined
3 valence electrons

21. Carbon Family C non-metal Si and Ge metalloids Sn and Pb metals
Except for water, most of the compounds in your body contain carbon
4 valence electrons

22. Nitrogen Family Wide range of properties
Includes Nitrogen and Phosphorus, two common components of fertilizers
Phosphorus by itself bursts into flame when it comes into contact with oxygen
5 valence electrons

23. Oxygen Family Oxygen is the most abundant element in Earth’s crust.
6 valence electrons
Sulfur used to make sulfuric acid, commonly used to make fertilizer

24. Halogens Family Highly reactive nonmetals
Ex: Fluorine, Chlorine, Iodine
Used in cleaners, toothpaste
7 valence electrons

25. Nobel Gases Colorless, odorless, extremely unreactive
Full valence shells
Emit colors when electric current is run through them.