Determination of Lewis Dot structures and visualization of the shapes of molecules using VSEPR theory is an example of an abstract concept that students often find difficult to learn. I have found it useful to have a single worksheet/packet that my students can add to as we cover Lewis dot structures, resonance, VSEPR shapes, polarity, and intermolecular forces.
In an effort to align an old VSEPR lesson to NGSS, I told my students that we were going to look at the data available from the real molecules on the pHET simulation we were using and specifically look for patterns. Finding patterns is a cross-cutting concept; one of the three dimensions of NGSS.
In this blog post, I'll discuss how I've expanded my use of model kits within my chemistry class to help explore a variety of topics with my students.
If you look at any chemistry textbook, you will see Lewis structures introduced long before electronic and molecular geometries. This makes sense since you need Lewis structures to determine molecular geometry. Unfortunately, research has shown that students often do not recognize that the purpose of drawing Lewis structures is not to create the structure itself but to use it as tool to understand the properties of the molecule (Cooper, Grove, Underwood & Klymkowsky, 2010).