CHM 130 The Lewis Structures & VSEPR Theory 3D Structure Lab Report

CHM130LLLab 10 – Lewis Structures and VSEPR Theory
Name: _________________________________________ MEID: ____________________
Complete the following items by typing into the text box provided. The boxes will increase in size if
additional space is necessary. Please be sure to save all your work as an MS Word document to
submit properly.
The following completed table serves as an example for the process you will follow in Part 1 of this
experiment.
Example Table:
ClO2-1 Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
ClO2-1
Chlorite ion
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (photo of molecule you
built)
2
2
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
Tetrahedral
Bent
Asymmetrical
Polar
Part 1:
Complete each data table according to the directions in the Lab 10 Procedures. Each photo is worth
3 points and all other entries on the data table are worth 0.5 points
CH4 Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
CH4
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (photo of molecule you
built)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
NH3 Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
NH3
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (photo of molecule you
built)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
H2O Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (photo of molecule you
built)
Electron Geometry
H2O
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
NH4+1 Data Table
NH4+1
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (photo of molecule you
built)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
H3O+1 Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
H3O+1
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (photo of molecule you
built)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
Part 2:
Complete each data table according to the directions in the Lab 10 Procedures. Each screenshot is
worth 3 points and all other entries on the data table are worth 0.5 points
NO3-1 Data Table
NO3-1
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (screenshot of the
molecule from website)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
HCl Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
HCl
Hydrochloric acid
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (screenshot of the
molecule from website)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
SO2 Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
SO2
3D Molecular Structure (screenshot of the
molecule from website)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
CO2 Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
CO2
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (screenshot of the
molecule from website)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
O2 Data Table
Molecule or Polyatomic Ion
Name of molecule or polyatomic ion
Lewis Structure
Number of Bonded Atoms on Central Atom
Number of Unshared (Lone) Pairs of Electrons
on Central Atom
3D Molecular Structure (screenshot of the
molecule from website)
Electron Geometry
Molecular Geometry (shape)
Is the molecule symmetrical or asymmetrical?
Is the molecule polar or nonpolar?
O2
Oxygen
C. Follow-Up Questions:
Part I
1. What information about a molecule can you gain from the Lewis structure? Be sure to answer
only in terms of the Lewis structure and not VSEPR theory. (2 pts)
2. Why can’t you determine the shape and polarity from Lewis structures alone? In other words,
why must you apply VSEPR theory to a Lewis structure to determine shape and polarity? (2
pts)
3. Many students acknowledge that constructing molecules helps them apply VSEPR theory to
two dimensional Lewis structures. Discuss TWO advantages you experienced as you
constructed three-dimensional models. (2 pts)
4. Explain how you used VSEPR theory to predict polarity. Your answer should include a
discussion of the connection between electron geometry, molecular geometry and symmetry.
Support your answer with examples from this lab. In other words, walk through the process
of using the two geometries and symmetry to show how you determined a polar molecule
was polar and a nonpolar molecule was nonpolar. (6 pts.)
5. Explain the difference in polarity between NH4+ and NH3 based on differences in their
electron geometries, molecular geometries and symmetries. (3 pts)
6. How are H3O+ and NH3 similar to one another? Base your response on similarities in their
electron geometries, molecular geometries and symmetries. (3 pts)
7. Why are the polarities of CO2 and SO2 different? Discuss similarities in their formulas and
differences in their electron geometries, molecular geometries and symmetries. (3 pts)
8. The solubility of a potential solute in a solvent depends on polarity. A rough rule of thumb
for solubility is “like dissolves like,” which means that substances with similar polarities will
form solutions (mix well together). Excluding polyatomic ions, choose TWO substances from
the lab that you think would mix well with water. Explain your choices in terms of the
substance and water polarities. (4 pts)
9. When mixed, oil and water do not form a solution (they do not mix well). What does this tell
you about oil’s polarity? Explain. Choose TWO substances from the lab that you think would
mix well with oil. Explain your choices in terms of the substances’ polarities. (6 pts)