1. CHAPTER 2

3. ELEMENTS: Periodic Table
____ total elements : ____ natural and ____ man-made

5. ORGANIZATION OF PERIODIC TABLE

6. ATOMIC STRUCTURE

7. How does an atom stay together?
THE NUCLEUS OF AN ATOM
How does an atom stay together?

8. ELECTRON ENERGY LEVELS

9. DIATOMIC ELEMENTS
Elements that must exist naturally as 2 atoms bonded together (until it forms a chemical bond with any other element)
Br I N Cl H O F
H N O F2 Cl Br I2

10. ISOTOPES

11. CHEMICAL BONDING

12. Bonding
Sodium is a silver-colored metal that reacts so violently with water that flames are produced when sodium gets wet. Chlorine is a greenish-colored gas that is so poisonous that it was used as a weapon in World War I. When chemically bonded together, these two dangerous substances form sodium chloride, a compound so safe that we eat it every day - common table salt! = +

13. IONIC BOND: Bohr Method
Bohr Model Method: Step 1: Draw the energy levels for each element Step 2: Show the arrow of transfer. There should be an arrow showing transfer for EACH electron given away. (Just like the top picture) Step 3: State the ions below each atomic structure to indicate that electrons have been gained or lost.

14. NaCl MgO IONIC BOND: Lewis Dot Structure
Lewis Dot Method: Step 1: Write the symbol for each atom separately and show valence electrons (evenly spread out ) Step 2: No arrows. Write ions once transfer has taken place. Show electrons for the ORIGINAL outer shell (the one that gained will show electrons).
Remember that ions are written as symbol with superscript.
NaCl
MgO

15. REDOX REACTIONS Reduction = gain electrons Oxidation = lose electrons

16. COVALENT BOND: Bohr Model
Bohr Model Method:
Step 1: Draw the energy
levels for each element
separately.
Step 2: Show the energy
levels joined (similar to
the top picture)
All diatomic elements
Demonstrate a
Covalent bond
Remember: BrINClHOF
(Chlorine is
shown to the
right)

17. COVALENT BOND: Lewis Dot Structure Molecular formula
Lewis Dot: Step 1: Draw the dot diagram for each element individually (use X and • for different atoms)
Step 2: Draw the dot diagram for the compound
Step 3: Show the molecular formula (including lone electrons)
Molecular formula

18. STATES OF MATTER Solid Liquid Gas
Definite shape Shape of container No definite shape
Definite volume Volume of container No def. volume
Tightly packed May overlap Very spread out
Vibrate in place Move faster Very fast

19. CHANGES IN STATE
2 types of Latent Heat = energy absorbed (stored) or released
Heat of fusion = energy released; Gas to Liquid to Solid
Heat of Vaporization = energy absorbed; Solid to Liquid to Gas

20. CHEMICAL EQUATIONS Reactant Reactant Product Product Reactant Reactant20

22. CHEMICAL REACTIONS Endothermic vs. Exothermic
Endothermic – energy absorbed – products have more energy than reactants
Exothermic– energy released – reactants have more energy than products

23. SECTION 3
WATER AND SOLUTONS
brass
bRONZE

24. 3
unique
characteristics
of water

25. POLARITY OF
WATER

26. HYDROGEN BONDING (Weak Bond)

27. Surface Tension is caused by…

28. COHESION / ADHESION / CAPILLARITY Cohesion attracts molecules of the same kind (water to water) Adhesion attracts molecules of different kinds (tape and hair) Capillarity is the attraction of molecules allowing a liquid to rise

29. SOLUTIONS
brass
bRONZE

30. THE DISSOCIATION OF WATER
Step 1: One water molecule bumps into another water molecule
Step 2: One of the water molecules dissociates (comes apart). When water dissociates, hydroxide ions (OH-) and a hydrogen ion (H+) are produced.

31. (Acid) (Base)---(Salt) (Water) If more hydroxide than hydrogen= BASE
ACIDS / BASES Acidity / Alkalinity depends on the amount of hydronium atoms.
HCl + NaOH        NaCl + H2O
(Acid) (Base)---(Salt) (Water)
If hydrogen=
hydroxide =
NEUTRAL
If more hydrogen than
hydroxide = ACID
If more hydroxide than hydrogen= BASE

32. TESTING FOR ACIDS / BASES