Name_____________________________________________________Date_______________________Per _________
#15
COVALENT BONDS: Notes, Practice and Marshmallow Lab
Part 1 - Notes
QUESTIONS
ANSWERS (use book (pp336-337) and my lecture notes)
COVALENT BONDS
1. What are Covalent Bonds?
2. Example and additional notes
on Covalent Bonds.
3. Properties of MOLECULES (Covalent
Molecules) (pp375-376
Review (some blanks may need more than one word)
Covalent bonds form between two or more _____________________________.
They will ___________________ electrons.
When ONE pair of electrons is shared this is called a __________ bond. When 2 pairs are shared this is a ___________bond.
We show covalent bonds with a ____________ between the atoms.
Part 2 - Practice
Molecule
water molecule (water is
H2O
EDD, # of atoms involved and, Bonds
# of
atoms
EDD
Natural gas (also called
methane) a covalent
compound used to heat
homes. The chemical
formula for natural gas is
CH4. Sketch a methane
molecule
Ammonia is a chemical
used in many cleaning
products. The chemical
formula for ammonia is
NH3. Sketch ammonia.
BONDS
To be
stable
# of
atoms
EDD
BONDS
To be
stable
# of
atoms
EDD
BONDS
To be
stable
Sketch of MOLECULE
When most things are
burned, they release
water and carbon dioxide
(CO2). Sketch a carbon
dioxide molecule. (hint:
there are two double
bonds)
Octane (C8H18) is the
main chemical in gasoline.
Sketch octane.
# of
atoms
EDD
BONDS
To be
stable
# of
atoms
EDD
Drag racers use methanol
(COH4) to fuel their race
cars. Sketch methanol
BONDS
To be
stable
# of
atoms
EDD
BONDS
To be
stable
Part 3 - LAB
Marshmallow Bonding
Cool!!! Now you’ve got it. Now let’s practice making some molecules.
Start with the chemical formula for each molecule. Get that many of each
“atom” from the supply station, and then try to put the molecule together
so that every atom has exactly the number of bonds that it wants. We’ll
start off easy and get a little harder as we go. When you are finished,
sketch the molecule that you made in the space provided
1. H2O (water)
2.
NH3 (ammonia)
3.
4.
H4CO (Methanol or racing fuel)
CO2 (carbon dioxide)
5.
C3H8 (Propane)
6.
C8H18 (Octane or Gasoline)
7. When octane is burned in a car’s engine, the atoms are rearranged to form CO 2 and water. Use as much oxygen as you
need to turn your octane model into CO2 and water.
a. How many water molecules did you make?
b. How many CO2 molecules are created for every octane molecule that is burned?
Bonus Questions:
I.
Make a glucose molecule
(C6H12O6)
II.
Make a benzene molecule
(C6H6)
Conclusion:
1. What is the difference between Ionic and Covalent bonding?
2. If a metal bonds with a nonmetal, what type of bond will form?
3. If a nonmetal bonds with another nonmetal, what type of bond will form?
4. Explain the difference between singles, double, and triple bonds.
5. Compare and contrast compounds with molecules.
6. Why do atoms form chemical bonds?