Lewis Structures
Name and Draw Lewis Structures
Name
Date
1. CBr4
7. NH3
2. SeF2
8. C2H6
3. SiO
9. CF2Br2
4. C3H8
10. SO42-
5. H2O
11. NH4+
6. CS2
12. Te3O
Period
The Name Is Bond – Chemical Bond
Problem:
Name_________________________
Data: Physical Characteristics of Three Unknown Substances
Substance Appearance (Naked
Relative
Solubility
Eye)
Melting Point
in Water
A
Electrical
Conductivity
Magnified
Appearance
B
C
Summing Up
1) How are the physical properties of the compounds A and B similar? How are they different?
2) Define the term electronegativity.
3) Find the table of electronegativities on page 263 of your text and answer the following:
a) Subtract the electronegativity of Na from that of Cl.
b) Subtract the electronegativity of C from that of H.
c) Compare the differences in your answers to (a) and (b.) Based on the definition of electronegativity
and the comparison you just made, what conclusions can you draw about the bond type that exists
between Na and Cl verses the bond type between C and H.
3) Is the sample C more like compound A or B? Justify your answer with your data.
Lewis Structures with Resonance: (Draw resonance structures where appropriate)
SO32-
CF3Cl
NH4+
CO2
HCN
HCO3-
CH3CH2Cl
NO3-
C2H4
CO32-
SO3
C2H2
Cl2
N2
CN-
O3
CH3CH2OH
SO2
Lewis Structures: Exceptions (Accelerated Only)
ClO2-
PCl5
BH3
SF6
NO2
I3-
C2H4
NO
NO2-
NO+
BeCl2
BF3
Naming Covalent Compounds
Write the formulas for the following covalent compounds:
1. antimony tribromide _______________
2. hexaboron monosilicide ______________
3. chlorine dioxide ___________________
4. iodine pentafluoride _________________
5. dinitrogen trioxide _________________
6. ammonia __________________________
7. phosphorus triiodide ______________
8. dinitrogen tetraoxide ________________
Name the following covalent compounds:
9. P4S5 ______________________________
10. O2 _________________________________
11. SeF6 _______________________________
12. Si2Br6 ______________________________
13. SCl4 _______________________________
14. CH4 ________________________________
15. B2Si _______________________________
16. NF3 ________________________________
Type
Formula
Name
(ionic, covalent, element or ion?)
1
MgO
2
P4S5
3
Fe
4
SeF6
5
CsNO3
6
SCl4
7
SO42-
8
Fe3+
9
NaC2H3O2
10
NF3
11
phosphorus tribromide
12
Copper (II) oxide
13
nitrate
14
phosphorus triiodide
15
iodine pentafluoride
16
Lead (IV) chloride
17
aluminum bicarbonate
18
dinitrogen tetraoxide
Formula
1
NH4Cl
2
B2Si
3
C3 P
4
Si2O6
Type
(ionic, covalent, element or ion?)
Name
5
oxygen difluoride
6
dinitrogen trioxide
7
berylium hydroxide
8
hexaboron monosilicide
9
chloride
10
chlorine
11
potassium sulfate
Name:________________________________
Date:_________________________________
Period:________________________________
Use your knowledge of Lewis structures and naming to complete the following table. Draw the molecule using
the Molecule Shapes simulation from the PhET website to complete the molecular information:
http://phet.colorado.edu/en/simulation/molecule-shapes.
Name
Formula
SCl2
ICl3
O3
SO3
C2H4
NO3-
TeCl4
OCS
Lewis
Structure
Molecular
Shape Name
3-D Molecular
Drawing
XeOF4
XeCl2F2
SCl3F3
C2H2Br2
-Win, Lose, or Draw
Problem: How does VSEPR theory determine the shapes of molecules? How does shape affect the polarity of
molecules?
Procedure
1) Assign a color of Dot to represent each of the elements in the data table (C, O, H, S, and P). Some
colors may represent more than one element
2) Draw the Lewis Structure for each of the molecules.
3) After you have done step two, use the appropriate dots and toothpicks to assemble a model of each
molecule. For single bonds, one whole toothpick represents a pair of electrons. For double
bonds, break a toothpick in half, each half represents one pair of electrons. For triple bonds,
break a toothpick into thirds, each third represents a pair of electrons. Complete for all of the
molecules in the table. (Do not disassemble models- in the end you will have 5 models.)
Data
Molecule
Lewis Structure
Name of Geometry
Molecular Geometry
SO3
PH3
H2O
CO2
C2H2
H2
Cl2
N2
Win, Lose or Draw
Name_______
Period___
Date_______
Summing Up
1) Contrast the Lewis structures of SO3 and PH3.
2) Contrast the geometries of SO3 and PH3. Why are they different?
3) In H2O, the oxygen (the central atom) has two hydrogens attached. In CO2, the carbon (the central
atom) has two oxygen atoms attached. Explain why the geometries of H2O and CO2 are different.
4) Summarize the effect of the presence of unshared electrons on the shape of a molecule.
5) Contrast the length of single, double, and triple bonds. Which bond type is strongest? Why?
Complete the table for each of the molecules.
Lewis Structure
PCl3
OF2
CO32-
SiS2
PO43-
HF
Name__________________
Name of Shape
Drawing of Shape
The following molecules are polar. Draw the molecules and then, using their electronegativities, and
include the δ+ and δ- ends.
H2O (bent)
HCl
OF2 (bent)
NH3 (trig. pyramidal)
The following molecules are NOT polar. Please tell why each molecule is not polar.
CCl4
O2
CO2
C2H6
Complete the chart:
Part 1: Identify the Bond Type in each molecule as ionic or covalent.
Part 2: For all covalent molecules, draw the molecular shape. If the molecule is polar, draw on
the partial charges.
Part 3: Classify all the covalent molecules as polar or nonpolar.
Bond Type
Polar or
(ionic or covalent)
If covalent, what shape? (with + or – if polar)
Nonpolar?
*if ionic, no shape or polarity
CaI2
Polar/Nonpolar
CBr4
Polar/Nonpolar
CH4
Polar/Nonpolar
Fe2O
3
Polar/Nonpolar
H2 S
Polar/Nonpolar
NF3
Polar/Nonpolar