Chemical Bonding Presentation PPTx Chapter 1

zzz

1. Chemical Bonding
Chapter 1
Interactions of Matter

2. REVIEW
Identify the 4 atoms whose models are on the
bulletin board.
How did you identify these elements?

3. Electron Arrangements
Energy LevelMaximum
Number of
Electrons
1 2
2 8
3 8 (then 10 more
later)
Remember
electrons
arrange in
energy levels
outside the
nucleus.

4. Electron Dot Diagrams
Show ONLY outer level electrons
Also called Lewis diagrams
1.Begin with the element’s symbol
2.Use the PT to determine the number of
outer level electrons
3.Place up to 2 dots per side for a total of up
to 8 electrons
 Put the first 2 dots together on one
side, then put single dots on the remaining
sides until you have to pair them

5. Electron Dot Diagrams
Ex: 1 electron
X

6. Electron Dot Diagrams
Ex: 2 electrons
X

7. Electron Dot Diagrams
Ex: 3 electrons
X
Choose a clockwise or counterclockwise
direction and fill empty sides with an
electron before pairing any electrons.

8. Electron Dot Diagrams
Ex: 4 electrons
X
Choose a clockwise or counterclockwise
direction and fill empty sides with an
electron before pairing any electrons.

9. Electron Dot Diagrams
Ex: 5 electrons
X
Choose a clockwise or counterclockwise
direction and fill empty sides with an
electron before pairing any electrons.

10. Electron Dot Diagrams
Ex: 6 electrons
X
Choose a clockwise or counterclockwise
direction and fill empty sides with an
electron before pairing any electrons.

11. Electron Dot Diagrams
Ex: 7 electrons
X
Choose a clockwise or counterclockwise
direction and fill empty sides with an
electron before pairing any electrons.

12. Electron Dot Diagrams
Ex: 8 electrons
X
THIS IS THE MOST ELECTRONS THAT EVER ARE
INCLUDED IN ELECTRON DOT DIAGRAMS.

13. Electron Dot Diagrams
Time to practice what you’ve learned
For the following elements, create electron dot diagrams
using M&M’s as electrons. Be sure to write large size
symbols on your paper.
YUM, but no eating allowed until all your work is
checked and is correct!
aluminum potassium argon oxygen
phosphorus silicon barium iodine
BRING IN YOUR ATOMIC MODEL TOMORROW!

14. CHEMICAL BONDING
The number of electrons in the ____________ energy
level determines whether an atom will form bonds.
These electrons are also called ___________ electrons.
Atoms bond to get a ________ outer level.
For all E levels beyond the first, the outermost E level is
considered to be full if it contains ______ (#) electrons.
The first E level is full with ____ (#) electrons.
Why are noble gases nonreactive?

15. CHEMICAL BONDING
Atoms bond by __________, ____________, or
___________ electrons to have a filled outermost
energy level containing 8 valence electrons.
___(#) types of bonds hold atoms together.
1.IONIC BOND- force of electrostatic attraction between 2
oppositely charged ______.
 Ions form when electrons are _________________.
2.COVALENT BOND- force of attraction between nuclei of atoms
and the electrons _______________ by the atoms.
 Neutral atoms held by covalent bonds are called
__________________.
3.METALLIC BOND- force of attraction between a ____________
charged metal ion and the electrons in a metal.

16. IONIC BONDS
Chem 4 Kids example
METALS
•have a low/high number of valence electrons.
•metals lose/gain electrons when bonding.
•form positive/negative ions.
NONMETALS
•have a low/high number of valence electrons.
•lose/gain electrons when bonding.
•form positive/negative ions.
•ions end in –ide

17. IONIC BONDS

18. Naming IONIC compounds
Binary compounds- contain only 2 elements
negative ion ends in -ide
Ex: Name NaCl
Ex: Name AlF
3
Ex: Name Li
2S
compounds are neutral so use subscripts to make (+)=(-)
Write the chemical formula for
Ex: strontium sulfide
Ex: potassium oxide
Ex: calcium chloride
Ex: barium nitride

19. Naming IONIC compounds
Binary compounds- containing transition elements
Transition metals- the charge is in parenthesis
following the name of the metal except for Ag, Cd,
and Zn (see PT)
ex: chromium (II) chloride

ex: iron (III) oxide

Ex:
NiF
2 vs.
NiF

Ex:
CrI
4 vs.
CrI
2

20. Naming IONIC compounds
What about compounds with more than 2 elements
Look on page 159 for polyatomic ions
Polyatomic ions- groups of atoms that are bonded
together with a charge
Usually end in -ate
Ex: BaSO
4
Ex: potassium phosphate
Ex: iron (III) carbonate

21. IONIC BONDS- metal ion + nonmetal ion
CHARACTERISTICS OF IONIC COMPOUNDS
•Hard, brittle solids at room temp
•High melting and boiling points
•Ions are held in a crystal lattice
•Conduct electricity when dissolved in H
2
O

22. Quick Review
1.Barium sulfide
2.Aluminum carbonate
3.NaClO
3
4.SiO
2
5.Dinitrogen pentoxide

23. COVALENT BONDS
Unlike ionic bonds with transferred electrons, covalent
bonds __________ electrons.
IONIC BOND COVALENT BOND

24. COVALENT BONDS
Unlike ionic bonds that generally form between metals
and nonmetals, covalent bonds form between
________________.
Classify the bonds as ionic or covalent
1.Na-Cl
2.H-O
3.C-O
4.Ca-F
5.N-N
6.Cr-S
NOTE: Group 14
has a strange e-dot
diagram

25. COVALENT BONDS
Use electron dot diagrams to model molecules
Examples:
1.H
2

2.H
2O
3.NH
3
4.Cl
2

26. COVALENT BONDS
Some molecules are simple with only one element
7 elements are not found in nature as atoms

They always are found in pairs- called diatomic
N
2
O
2
F
2
Cl
2
Br
2
I
2
And H
2 (always the exception)

27. COVALENT BONDS
EXAMPLES OF COVALENT COMPOUNDS
water
plastic
sugar
Gasoline oils & fats
CHARACTERISTICS OF COVALENT COMPOUNDS
1.Do NOT conduct an electrical current
2.Low melting and boiling points
3.Lightweight molecules: generally gases and liquids at
room temp
4.Heavier molecules: generally solids at room temp

28. COVALENT COMPOUNDS
Naming covalent compounds involves using prefixes to
indicate the number of atoms in the formula.

Website w/prefixes and rules

29. COVALENT COMPOUNDS
•When atoms share electrons, they don’t
always share them equally.
•Nonpolar covalent compounds:
share e- equally
•Will not conduct an electrical
current at all
•All diatomic molecules are
nonpolar
•Polar covalent compounds: share e-
unequally
•Can conduct an electrical current

30. COVALENT COMPOUNDS
•Polarity affects how chemicals mix.
•“Like dissolves like.”
•Nonpolar compounds mix with other
nonpolar compounds.
•Ex:
•Polar compounds mix with other polar
compounds.
•Ex:
•Nonpolar compounds will not mix with
polar compounds.
•Ex:
•How does this affect how soap is made?

31. METALLIC BONDS
EXAMPLES CONTAINING METALLIC BONDS
Cu, Fe
Alloys- mixtures of metals
 EX: brass, bronze, steel
CHARACTERISTICS OF METALS
1.Malleable & ductile
2.Good conductors
“sea of electrons” allows metals to be shaped without
breaking
Close metal atoms have overlapping outer E levels
Valence electrons can move freely between positive metal
ions