Chemical Bonds, Forces and Models

A series of free High School Chemistry Video Lessons.

In this lesson, we will learn

• Hybridization
• Intermolecular Forces
• VSPER Model

Hybridization
Hybridization occurs when an atom bonds using electrons from both the s and p orbitals, creating an imbalance in the energy levels of the electrons. To equalize these energy levels, the s and p orbitals involved are combined to create hybrid orbitals. Hybridization is a key concept in valence bond theory, but alternate models are proposed in molecular orbital theory.
How to predict the hybridization of atomic orbitals. Hybridization
Orbital hybridization is discussed and used as an explanation for the bonding seen in various molecules. Intermolecular Forces
Intermolecular forces are forces that hold two molecules together. Dispersion forces (also called Van der Waals Forces) act on all molecules and are the only forces between two non-polar molecules. Two polar molecules are held together by the electrostatic attraction between their dipoles in dipole - dipole force. The strongest type of intermolecular force is hydrogen bonding.
Understanding the forces acting between molecules. This lesson discusses what intermolecular (van der Waals) forces are and why they occur. We look at Dipole-Dipole interactions, Hydrogen bonding and London Dispersion Forces. The strength of an intermolecular force is related to the polarity of the molecules.

VSPER Model
The VSEPR model stands for Valence Shell Electron Pair Repulsion model. The VSEPR model is a model which predicts the geometrical shapes of molecules based on the repulsion between their lone pairs. Types of VSEPR structures include linear, trigonal planar and tetrahedral.
How to draw the structure of a molecule using VSPER rules. This is an introduction to the basics of VSEPR Theory. VSEPR theory is a set of rules for how to look at a Lewis structure and determine the three dimensional (3D) shape of a molecule. The shapes have to do with the location of bonds and lone electrons pairs. In this video, we'll look at the following shapes: linear, trigonal planar, bent, tetrahedral, and trigonal bipyramidal


VSEPR Theory Practice Problems
Lots and lots of practice problems for VSEPR theory. We will look at how to take a Lewis structure and determine what the 3D shape of the molecule will be. Here are the shapes that we will talk about: tetrahedral, trigonal pyramidal, bent, trigonal planar, linear. We will also talk about angles in degrees: 109.5º, 107º, 105º, 120º, 180º and 116º and amounts that are less. VSEPR Theory: Common Mistakes
Don't make these common mistakes with VSEPR! We'll talking about how to determine the shape or geometry of a molecule using the VSEPR rules, for valence shell electron pair repulsion. Unshared electron pairs (also known as lone pairs) are very important for determining geometry, and we'll look at the following shapes: tetrahedral, trigonal planar, trigonal pyramidal, linear, and bent.