Applying Modeling Instruction to High School Chemistry To Improve Students’ Conceptual Understanding
Larry Dukerich has been using Modeling Instruction for many years. He is a founding member of the AMTA.
Abilities Necessary to do Scientific Inquiry
Colorful Lather Printing
In this Activity, students marble paper with shaving cream and food color while exploring water, polarity, and hydrophilic and hydrophobic materials. Although the Activity is familiar, it contains a new twist—exploring how a colored shaving cream mixture behaves when a drop of water is added. This Activity can be used to introduce the concepts of polarity, soaps, and surfactants.
How Does Your Laundry Glow?
In this Activity, students examine the effect of pH on the intensity and color of the emission of fluorescent dyes in liquid laundry detergent. They perform two titrations using vinegar to estimate the pH at which the fluorescence properties change. In the second titration, sodium bicarbonate is added to buffer the detergent solution.
Mass Spectra
In this Activity, students solve puzzles that are analogous to finding the amino acid sequence of a peptide using mass spectrometry. Students identify words that have been broken into letters or groups of letters. In many textbooks instrumental analysis and various types of spectrometry are mentioned only in passing.
Fluorescent Fun: Using a Homemade Fluorometer
In this Activity, students investigate the fluorescence of highlighter marker ink and the principles employed in studying fluorescent molecules using a homemade fluorometer and different colored filters.
Flipping Pennies and Burning Candles: Adventures in Kinetics
In this Activity, students collect data to determine whether two processes, flipping pennies and burning small birthday candles, follow zeroth- or first-order rate laws. Students first collect data on the number of pennies remaining "heads up" after several successive tosses and then measure the mass of a burning candle over time.
Testing for Iodide in Table Salt
In this Activity, students use supermarket chemicals to test samples of table salt for the presence of iodine, an essential micronutrient added as iodide ion. The presence of iodide in the salt is made apparent by the appearance of a blue color.
Out of the Blue
In this Activity, students first prepare a standard formulation for a variation on the classic blue bottle reaction using consumer chemicals. They then make appropriate changes to the formulation and observe the results to determine the roles played by each reactant. This Activity could be used with units on chemical kinetics and oxidation-reduction reactions.
Hold the Heat: Global Warming and Calorimetry
In this Activity, students perform quantitative calorimetric measurements on samples of ice/water heated by incandescent light bulbs and/or convection with room-temperature surroundings. They measure and graph temperature as a function of time.
Pondering Packing Peanut Polymers
In this Activity, students compare polystrene and cornstarch packing materials ("peanuts"). Both are made of polymers, but because of their composition, they behave very differently in various solvents. Students extrapolate how these differences in behavior relate to environmental effects, such as filling landfills with non-biodegradable materials.