Interaction of Energy and Matter

How a Photon Is Created or Absorbed

Giles Henderson
Eastern Illinois University, Charleston, IL 61920

Robert C. Rittenhouse
Walla Walla College, College Place, WA 99324

John C. Wright and Jon L. Holmes
University of Wisconsin-Madison, Madison, WI 53706

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.

Some Like It Hot, Some Like It Cold

In this Activity, students combine liquids in a calorimeter and use a thermometer to determine if the reaction mixture gets hot or cold. All of the chemicals (yeast, hydrogen peroxide, vinegar and baking soda) except ammonium nitrate, are available in supermarkets.

Calories - Who's Counting?

In this Activity, students determine how many calories are released per gram when marshmallows and cashews burn and then compare the quantity of energy available from carbohydrates versus fats. Students burn the food items beneath a metal soft drink can containing water and measure the resulting change in temperature of the water.

Flame Tests: Which Ion Causes the Color?

In this Activity, students perform simple flame tests using eleven commercially available compounds, cotton swabs, and a Bunsen burner. They then determine whether the cations or anions in each compound are responsible for the flame test colors. This Activity introduces students to flame tests in an inquiry-based manner.

Turning on the Light

In this Activity, students investigate the luminescent properties of common items such as glow-in-the-dark stickers, wintergreen-flavored hard candies, and a chlorophyll solution made from spinach leaves. After making observations, they use a flowchart to categorize the luminescent items as fluorescent, phosphorescent, or triboluminescent.

Colors in Liquid Crystals

In this Activity, students investigate the relationship between temperature and composition and the reflected and transmitted colors of a common nanoscale material, the cholesteric liquid crystal.

Memory Metal

In this Activity, students compare the properties of nitinol metal wire (known as "memory" metal) and ordinary wire. Using the observed properties, they design (and possibly make) a toy that would use memory metal to operate. This Activity connects toys with science, and allows students to become inventors as they design a toy of their own.

Popcorn: What's in the Bag?

In this Activity, students investigate microwave popcorn, the process of microwave-promoted popping, and the materials involved: water, vegetable oils, starch, and special packaging materials. This Activity supports discussion of thermal and electromagnetic energy, phase changes, intermolecular forces, patterns of solubility, and the structure of fats, oils and starches.