1. Periodic Table
PS-2.3 Explain the trends of the periodic table based on the elements’ valence electrons and atomic numbers.
PS-2.5 Predict the charge (oxidation numbers) that a representative element will acquire according to the arrangement of electrons in its outer shell.

2. What are the three subatomic particles of the atom?
Proton
Electron
Neutron

3. What are the charges of each?
Protons  Positive
Electrons  Negative
Neutron  Neutral

4. What are the charges of each?
Protons  Positive
Electrons  Negative
Neutron  Neutral

5. What particles form neutrons and protons?
Quarks

6. Where are each located? Proton  inside the nucleus
Neutron inside the nucleus
Electron  outside the nucleus
Electron Cloud

7. What is the net charge of the nucleus?
Positive

8. What determines the identity of the atom?
Protons

9. History of the Periodic Table
1871: Dimitri Mendeleev
Organized elements together that had similar properties.
Developed the Periodic table.

10. The Periodic Table

11. Period Horizontal row on the periodic table
Period # = the number of energy levels an element occupies

12. # of energy levels
From left to right: atoms in the same period contain the same number of energy levels
Energy levels increase as you move down the periodic table

13. Group/Family Vertical column on the periodic table Similar Chemistry
Ex: Cu, Ag, Au – shiny metals, good conductors

14. Group/Family Names Group/Family Name Valence Electrons 1 Alkali Metals2
Alkaline Earth Metals 13 3 14 4 15 5 16
Oxygen Family 6 17
Halogens 7 18
Noble Gases
8 (except He)

15. Categories Metals Nonmetals Metalloids
Shiny exist as solids at room temp
good conductors
Nonmetals
Gasses or brittle solids
Not conductors
Metalloids
Elements that contain properties of metals and nonmetals

17. Group (family) Group # = element’s valence electrons Valence electrons
electrons in the outer most energy level
determines chemical properties of the element.
Each row ends with the outer energy level filled.

18. Number of Valence Electrons
Valence electrons increase by one from left to right across the periodic table
From top to bottom in a group: atoms in the same group contain the same number of valence electrons

20. Group (family) Each group has the same Lewis Dot structure
Shows the number of valence electrons for each element

22. Reading the Periodic Table
Chemical Symbol
Name
Atomic #: tells the # of protons
Atomic Mass: Average of all isotopes of an atom
Mass #: Protons + Neutrons

23. Chemically Stable Atoms
Noble gases are the only chemically stable atoms
They have a full outer energy level
Ex. Neon 8 valence e-
Helium 2 valence e-

24. Chemical Stability
Atoms that do not have a full outer energy level tend to gain, lose, or share valence electrons in order to become stable.
Chemical reactions
electrons being gained, shared, or lost
the number of protons, and neutrons stay the same.

25. Becoming stable Group 1 tends to lose 1 electron.
Group 2 tends to lose 2 electrons.
Group 16 tends to gain 2 electrons.
Group 17 tends to gain 1 electron.
Group are less likely than the above to gain or lose electrons.
Groups tend to lose electrons.

26. If a neutral atom… A charged particle is called an Ion.
Oxidation State: number of a electrons an atom will gain/lose to become stable
Loses electrons: forms a positive ion. (metals)
Gains electrons: forms a negative ion (nonmetals)

28. Diatomic Molecules
7 elements that are so reactive they covalently bond to themselves to form a molecule
Only when free in nature