AT CHEMISTRY
Szkolar/Levine
MOLECULAR ARCHITECTURE
BUILDING MOLECULAR MODELS
In this lab investigation you will build models of a variety of molecules based on their
Lewis structures taking into consideration VSEPR theory and orbital hybridization. In order to
determine which "atoms" to use in constructing your models, you must first draw the Lewis
structure (on a separate sheet of paper) and then determine the hybridization of the central atom.
Based on the hybridization, choose the appropriatete atom (color). If there are two or more
nonequivalent Lewis structures, determine the best one using formal charge.
Work in pair. The inside of your model kit contains a parts code including the
hybridization(s) possible. Use appropriate model bond color in connecting atoms. The beige
plastic plates represent nonbonding (lone) pairs.
Once you have determined the correct Lewis structure and built the model, draw its
Lewis structure on the lab sheet.
Atom
color
use
angle
H
Be
S
S
C
C
P
S
S
white
grey
yellow
black
black
black
black
yellow
grey
sp
sp
sp2, sp3
sp2
sp3
sp2
dsp3
sp3
sp3, d2sp3
180o
120o, 109.5o
120o
109.5o
120o
90o, 120o
109.5o
109.5o, 90o
etc.
bonds
single
double
triple
white or green linerar pegs
curved blue
curved blue
lone (nonbonding pairs):
blue or green playes
1
note:

The number of electron pairs referes to the number of effective electron pairs around the
central atom.

 bonds and  bonds refer to the total number of each in the entire molecule.

Electron pair geometry refers only to the electron pair geometry based only on the
number of effective pairs around the central atom (without considering bonding and
nonbonding pairs)/

Molecular geometry refers to the geometry of the actual molecule taking into account
bonding and nonbonding pairs.

For thjose molecules that can be represented by more than one structure, draw the best
one vbased on formal charge.
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MOLECULAR ARCHITECTURE
BUILDING MOLECULAR MODELS
Name___________________
1. Chemical Formula: BeCl2
CENTRAL ATOM EFFECTIVE PAIRS
Number of electron pairs:
Bonding pairs:
Nonbonding pairs:
Electron Pair geometry:
Lewis Structure:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
2. Chemical Formula: SO3
 bonds:
Number of electron pairs:
Bonding pairs:
Lewis Structure:
 bonds:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
3
3. Chemical Formula: SO2
Number of electron pairs:
Lewis Structure:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
4. Chemical Formula: SO32- (draw best structure based on formal charge)
Lewis Structure:
Number of electron pairs:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
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5. Chemical Formula: CH4
Number of electron pairs:
Bonding pairs:
Nonbonding pairs:
Lewis Structure:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
6. Chemical Formula: H2O
 bonds:
Number of electron pairs:
Bonding pairs:
Lewis Structure:
 bonds:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
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7. Chemical Formula: O3
Number of electron pairs (around central O):
Bonding pairs:
Nonbonding pairs:
Lewis Structure:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
8. Chemical Formula: H2O2 (HOOH)
 bonds:
 bonds:
Number of electron pairs around one of the
O’s:
Lewis Structure:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of O atom:
Bond angles:
Polarity:
 bonds:
 bonds:
______________________________________________________________________________
9. Chemical Formula: PCl5
Number of electron pairs:
Lewis Structure:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
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10. Chemical Formula: SF4
Number of electron pairs:
Lewis Structure:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
______________________________________________________________________________
11. Chemical Formula: ClF3
Number of electron pairs:
Lewis Structure:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
______________________________________________________________________________
12. Chemical Formula: XeF2
Number of electron pairs:
Bonding pairs:
Lewis Structure:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
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13. Chemical Formula: BrF5
Number of electron pairs:
Lewis Structure:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
______________________________________________________________________________
14. Chemical Formula: I3-
Number of electron pairs:
Bonding pairs:
Nonbonding pairs:
Lewis Structure:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
______________________________________________________________________________
15. Chemical Formula: HNO2 (acid) note: the H is bonded to an O in oxyacids
Lewis Structure:
Number of electron pairs (ONO):
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of N atom:
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Bond angles:
Number of electron pairs (NOH):
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of O atom:
Bond angles:
Overall polarity:
 bonds:
 bonds:
16. Chemical Formula: CH3COCH3
Number of electron pairs:
Lewis Structure:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Overall polarity:
 bonds:
 bonds:
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COMPLEX IONS (the anion is bonded to the cation via single bonds)
17. Chemical Formula: Fe(CN)63(C of CN bonded to Fe)
Lewis Structure:
Number of electron pairs:
Bonding pairs:
Nonbonding pairs:
Electron pair geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
ion name:
18. Chemical Formula: CuCl42-
Number of electron pairs:
Bonding pairs:
Nonbonding pairs:
Lewis Structure:
Electron air geometry:
Molecular Geometry:
Hybridization of central atom:
Bond angles:
Polarity:
 bonds:
 bonds:
ion name:
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