Identification of polar and nonpolar molecules Flashcards
How can you determine if a molecule is polar or nonpolar?
A molecule is polar if it has a net dipole moment, which means that there is an uneven distribution of electron density across the molecule.
Polar molecules usually have polar bonds and an asymmetrical shape, causing them to have net dipole moments. Nonpolar molecules, on the other hand, are usually symmetrical resulting in canceled dipole moments.
Is carbon dioxide (CO2) considered a polar or nonpolar molecule?
nonpolar molecule
The linear shape of CO2 causes the dipole moments of the two C=O bonds to cancel each other out.
Why is water (H2O) considered a polar molecule?
Water is polar because its bent shape results in an uneven distribution of electron density, with the oxygen atom being partially negative and the hydrogen atoms being partially positive.
The bond angle of approximately 104.5 degrees creates a net dipole moment, as the polar O-H bonds do not cancel each other out.
How does the symmetry of a molecular structure affect its polarity?
Symmetrical molecules tend to be nonpolar, while asymmetrical molecules tend to be polar.
Even though a molecule contains polar bonds, a symmetrical arrangement like in tetrahedral, trigonal planar, and octahedral shape can result in a nonpolar molecule because the dipole moments cancel out.
How does the molecular shape of sulfur hexafluoride (SF6) affect its polarity?
SF6 is nonpolar because its octahedral geometry allows the cancellation of the dipole moments of the S-F bonds.
Despite each S-F bond being polar, the symmetrical arrangement of F atoms around the sulfur atom ensures that the dipole moments cancel each other, resulting in a nonpolar molecule.
