Honors Chemistry
Name ________________________
Per ______ Date ________________
Lab 6-1: Molecular Theories and Shapes
Background: Using VSEPR, shapes of molecules can be predicted because electron pairs (sigma bonds
and nonbonding electron pairs) want to arrange themselves as far apart as possible. Hybridization theory
predicts that hybridized atomic orbitals, which can either form sigma bonds or hold nonbonding electrons,
will orient themselves so that they also have a maximum separation. Hybridization of a central atom can be
determined by counting sigma (single) bonds + nonbonding electron pairs.
Bonds + pairs
2
3
4
5
6
hybridization
sp
sp2
sp3
sp3d
sp3d2
Purpose: you will use VSEPR and hybridization theory to explain various molecular geometries and also
to determine the shape of several molecules.
Materials: computer with access to Internet, brain
Procedure:
1) Copy the charts in the data section into your lab book. Leave enough space for drawings were indicated.
2) On the day of the lab, you will access:
https://s3.amazonaws.com/files.haikulearning.com/data/SaddleSpace/minisite_2605037/7eb2366468/index.
html
or
find the link on my Haiku website.
3) On the day of the lab, complete Charts 1 & 2 (NOTE: not all of the molecules you need to identify will
be on the computer). Also, obtain Lab 6-1, sheet 2 from your instructor. Copy the formulas for the
unknown molecules onto your data chart (Chart 3) and complete the rest of the chart using the information
you just completed. BE AS PRECISE AS POSSIBLE.
4) Hitting the escape (Esc) key will stop the molecule from rotating. To restart the molecule, use the
Reload or Refresh option from the menu bar.
5) NOTE: Ideal bond angles are 90o, 109.5o, 120o, and 180o ONLY
6) Exit all programs and shut down the computer. Complete the conclusion questions.
Data:
NOTE: A = central atom X = atom bonded to central atom
e = nonbonding electron PAIR around central atom
Copy the following data charts into your lab notebook.
Chart 1 (Use a whole page in your notebook)
Molecule Type
AX2
AX2-e
AX2-2e
AX2-3e
AX3
AX3-e
AX3-2e
AX4
AX4-e
AX4-2e
AX5
AX5-e
AX6
Chart 2
Molecule Type
AX2
AX2-e
AX2-2e
AX2-3e
AX3
AX3-e
AX3-2e
AX4
AX4-e
AX4-2e
AX5
AX5-e
AX6
Shape (name)
Drawing
Ideal Bond
Angle(s)
Hybridization
around central atom
Chart 3 (use a whole page in your notebook) See Sheet 2
Formula of Molecule
Lewis Structure (Drawing)
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
13)
Shape (name)
Conclusions:
1) Assuming that all bonding atoms (X) are the same and that all bonds between A and X
are polar, which type of molecules (Chart 2) would be polar?
2) Predict the shapes of the following molecules: (HINT: count sigma bonds and
nonbonding pairs, then determine the hybridization of the central atom)
a) AX3-3e
e) AX-4e
b) AX-e
f) AX-5e
c) AX-2e
g) AX2-4e
d) AX-3e
3) What effect do nonbonding electron pairs around the central atom have on the actual
bond angles?
4) Why can atoms in the third row form expanded octets, while elements in the second
row cannot?
Honors Chemistry
Name ________________________
Per ______ Date ________________
Lab 6-1: Sheet 2
1) H2S
2) BeF2
3) SF6
4) SCl4
5) XeF2
6) GeF2
7) CCl4
Honors Chemistry
8) NH3
9) SO3
10) PF5
11) XeCl4
12) ClF5
13) ClF3
Name ________________________
Per ______ Date ________________
Lab 6-1: Sheet 2
1) H2S
2) BeF2
3) SF6
4) SCl4
5) XeF2
6) GeF2
7) CCl4
Honors Chemistry
8) NH3
9) SO3
10) PF5
11) XeCl4
12) ClF5
13) ClF3
Name ________________________
Per ______ Date ________________
Lab 6-1: Sheet 2
1) H2S
2) BeF2
3) SF6
4) SCl4
5) XeF2
6) GeF2
7) CCl4
8) NH3
9) SO3
10) PF5
11) XeCl4
12) ClF5
13) ClF3