Name: __________________________
Date: ______________ Period: _______
Computer#: __________
MOLECULAR GEOMETRY, LEWIS STRUTURES AND VSEPR Std 2F
Zumdahl CD
1. Select “Chapter 11” from the main “Contents Menu”
2. Select “Exploration” from the “Overview Menu”
3. Select “The VSEPR Theory of Molecular Structure” from the window that comes up.
4. In the “Exploration” section read screens 1-4 and then copy the chart on page 5.
5. On page “5 of 6” copy the chart showing the various shapes you will get given the
Sets of Electron Bonding Pairs and Unshared pairs.to check out your Lewis Structure for
correctness.
6. On page “6 of 6” you will find “buttons” for 25 molecules. Do the first 24 but DO NOT DO
#25. Numbering of molecules is top row left to right (1-6), 2nd row left to right (7-12), and
so on. List each molecular formula, its Lewis structure, shape (bent, linear, tetrahedral,
trigonal planar or trigonal pyramidal) and why it is the shape your say it is. You should click
on “Examine Lewis Structure” to be sure you wrote it correctly. You should also click on
“Examine molecular shape”. Under the “Display” menu at the top choose “Ball and
Stick” option and then rotate the molecule to see how it is shaped.
Note: an X after the number for a molecule means that the Lewis Structure on the CD is wrong
and you will need to fix it.
Molecule
Lewis Structure
Shape
Why this shape?
BeF2
Straight, or linear
No unshared pairs on the central atom,
2 electron pairs on central atom
BeH2
Straight, or linear
No unshared pairs on the central atom,
2 electron pairs on central atom
BF3
Trigonal planar
No unshared pairs on the central atom,
3 electron pairs on central atom
BH3
Trigonal planar
No unshared pairs on the central atom,
3 electron pairs on central atom
CCl4
Tetrahedral
4 atoms around the central atom, no
unshared electron pairs on central atom
CH4
Tetrahedral
4 atoms around the central atom, no
unshared electron pairs on central atom
CO2
Straight, or linear
No unshared pairs on the central atom,
2 electron pairs on central atom
1.
2.
3.
4.
5.
6.
7.X
8.
2CO32-
Trigonal planar
No unshared pairs on the central atom,
3 electron pairs on central atom
9.
F2O
Bent, or V-Shaped 2 unshared pairs on the central
atom, 4 electron pairs on central
atom
H2O
Bent, or V-Shaped 2 unshared pairs on the central
atom, 4 electron pairs on central
atom
H2S
Bent, or V-Shaped 2 unshared pairs on the central
atom, 4 electron pairs on central
atom
HCN
Straight, or linear
ICl21+
Bent, or V-Shaped 2 unshared pairs on the central
atom, 4 electron pairs on central
atom
NH3
Trigonal planar
10.
11.
12.
No unshared pairs on the central
atom, 2 electron pairs on central
atom
13.
14.
No unshared pairs on the central atom,
3 electron pairs on central atom
15.X
NO21-
Bent, or V-Shaped 1 unshared pair on the central atom,
O3
Bent, or V-Shaped, 1 unshared pair on the central atom,
3 electron pairs on central atom
also resonant
3 electron pairs on central atom
16.X
17.
PCl3
18.
Trigonal pyramid
One unshared pair on the central atom,
4 electron pairs on central atom
Tetrahedral
4 atoms around the central atom, no
unshared electron pairs on central atom
3PO4
3-
19.
4 atoms around the central atom, no
unshared electron pairs on central atom
POCl3
Tetrahedral
SF2
2 unshared pairs on the central atom,
Bent, or V-Shaped 3 electron pairs on central atom
SiCl4
Tetrahedral
20.
21.
4 atoms around the central atom, no
unshared electron pairs on central atom
22.X
SO2
Bent, or V-Shaped 1 unshared pair on the central atom,
SO3
Trigonal planar,
and resonant
No unshared pairs on the central atom,
3 electron pairs on central atom
Tetrahedral
4 atoms around the central atom, no
unshared electron pairs on central
atom
3 electron pairs on central atom
23.
24.
2SO42-
NOTE: When counting electron pairs around the central atom, both double and triple bonds
count as only one electron pair when predicting shapes.