Question

For the following compounds: PCl3, PCl5, POCl3. Draw a Lewis structure for each molecule in the gas phase. State the shape of each molecule and predict the bond angles. Deduce whether or not each molecule is polar, giving a reason for your answer.

A) Not applicable (text-based question)
B) Explanation of molecular geometry and polarity
C) Molecular properties of PCl3, PCl5, POCl3
D) Can't be determined

Answer 1

The Lewis structures, shapes, bond angles, and polarities of PCl3, PCl5, and POCl3 are provided. PCl3 and POCl3 have polar bonds and are polar molecules due to the presence of lone pairs. PCl5, on the other hand, has polar bonds but is a nonpolar molecule due to its symmetric structure.

Step-by-step explanation:

The Lewis structures and molecular properties of the compounds PCl3, PCl5, and POCl3 are as follows:

1. PCl3
   Lewis Structure:
   Shape: Trigonal Planar
   Bond Angles: 120°
   Polar: Yes, because of the lone pair on the phosphorus atom.
2. PCl5
   Lewis Structure:
   Shape: Trigonal Bipyramidal
   Bond Angles: 90° and 120°
   Polar: No, because the bond dipoles cancel each other out due to the symmetry of the molecule.
3. POCl3
   Lewis Structure:
   Shape: Trigonal Pyramidal
   Bond Angles: 109.5°
   Polar: Yes, because of the lone pair on the phosphorus atom.

The primary topic of this question is the molecular geometry and polarity of compounds.