Science Practice: Developing and Using Models

Stop Motion Animation Galvanic Cell Process

With few materials available to complete wet labs in my school, I have to be creative with covering lab concepts in my AP chemistry course. I was looking for a way to make sure my students were getting the idea of the macroscopic changes that take place in a galvanic cell without necessarily being able to do the wet lab. The particulate model that is part of the Energizer Lab inspired me to write an end of unit assignment for my students using Stop Motion video apps.

The Liquid Nitrogen Cloud

Have you ever seen the liquid nitrogen cloud? Do you wonder how the cloud forms when hot water is thrown onto liquid nitrogen? This post explores the liquid nitrogen cloud and possible explanations for its formation.

M&Ms as Isotopes

Use Mega M&Ms, M&Ms minis, and regular M&M’s in this activity to examine the concept of isotopes and average atomic mass. The color of the M&M’s represent that they are the same element and have the same number of protons. The size represents, in a relative sense, the different numbers of neutrons.

Equilibrium Snowball Fight

For dynamic equilibrium, I like to use a physical analogy that pits students against each other in a classroom-wide “snowball” fight. Not only is this activity great for building students’ conceptualization of dynamic equilibrium, it is also really fun!

Measuring Surface Tension to Investigate Intermolecular Forces

Like most concepts in chemistry, intermolecular forces takes a bit of imagination and critical thinking to fully comprehend and apply when explaining a variety of situations. Though demonstrating the presence of these forces in a simple and explicit manner can easily be done, I wanted to change how I introduced IMFs a bit this year by focusing on a more data-to-concepts approach.

Lewis Dot, VSEPR Shape, Polarity and Intermolecular Forces Activity Sheet

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.

Elements, Compounds, and a Vocabulary Card Sort

How many of you could recite, word for word, a definition you learned in school? When you first memorized the definition, you could state “inertia is a property of matter”, or “density is mass over volume.” However, you struggled to apply it to a new situation and maybe you were unsure of how to construct a model of what it meant.