10: Review
- Page ID
- 42943
Introduction
In the first part of Gen Chem 2 we will predict physical properties of matter like boiling/melting points, and physical behavior like predicting if two substances will mix with each other. The class will start by quickly reviewing intermolecular forces, which require knowing if a substance is polar or not. This review section contains material from General Chemistry 1 that you need to know for General Chemistry 2, but which General Chemistry 2 will not cover. Specifically, you need to review Lewis Dot Structures, Molecular Geometries and predicting if a molecule is polar. Here is an outline to give you a big picture perspective on why we need to review this.
- Physical properties and behavior are influenced by the types of intermolecular forces matter has.
- Determining intermolecular forces requires identifying if a molecule is polar or not.
- Determining polarity requires knowing the geometry of the molecule.
- Determining the geometry requires knowing the Lewis dot structure.
So the workflow for predicting a molecules properties and behavior sort of follow the above in reverse order.
Step 1: Determine Lewis Dot Structure (where are the bonds and where are the lone pairs of electrons)
Step 2: Determine the Molecular Geometry (using VSEPR)
Step 3: Determine molecular polarity from bond polarities and molecular symmetry
This review will have 3 sections that relate to this workflow (10.1, 10.2 & 10.3). Each section is a very brief summary of key concepts with links to the relevant General Chemistry 1 chapters. This material will not be covered in lecture, but you are expected to know it, and it is fair material for exams and quizzes..
Contributors and Attributions
- Bob Belford