Effect of Molecular Geometry on Polarity

For each molecule:
• Sketch each molecule as shown in the simulation.
• Include arrows to show the bond dipoles as well as a molecular dipole (if present).
• Circle polar or nonpolar to indicate the polarity of the molecule.
• Name the molecular geometry (from Part A)

a. H2O vs CO2
H2O CO2

polar nonpolar polar nonpolar
Molecular Geometry Molecular Geometry
Question 1a: How does the molecular geometry (linear vs bent) affect the molecular polarity?

b. NH3 vs BH3
NH3 BH3

polar nonpolar polar nonpolar
Molecular Geometry Molecular Geometry
Question 1b: How does the molecular geometry (trigonal pyramidal vs trigonal planar) affect the polarity?

Effect of Differences in Electronegativity on Molecular Polarity
For each molecule:
• Sketch each molecule as shown in the simulation.
• Include arrows to show the bond dipoles as well as a molecular dipole (if present).
• Circle polar or nonpolar to indicate the polarity of the molecule.
• Fill in the electronegativity values for each atom

c. O2 vs HF
O2 HF

polar nonpolar polar nonpolar
Electronegativity O = H= F =
Question 2a: Both of these molecules have the same molecular geometry; they are linear. How do differences in electronegativity affect the molecular polarity in linear molecules?

d. CH4, CH3F, and CHF3
CH4
CH3F
CHF3

polar nonpolar polar nonpolar polar nonpolar
Electronegativity C= H= C= H= F= C= H= F=
Question 2b: All three of these molecules have the same molecular geometry; they are tetrahedral. Observe the collection of bond dipoles and explain why they do not all have the same molecular polarity

Sample Solution