first-year undergraduate

Ramping Up the Disappearing Rainbow with the Assassin’s Water Bottle

What happens when chemistry and illusion collide? In The Disappearing Rainbow, a simple acid–base demonstration transforms into a spellbinding performance. With a single pour, colorless liquids bloom into a vibrant rainbow—then vanish in an instant. Now, with the arrival of the “Assassin’s water bottle,” this classic demo gets a modern twist that makes the magic easier (and cleaner) than ever.

Three Turmeric Treats

Curcumin, found in the spice turmeric, varies from yellow in acidic conditions to orange-red in basic conditions. This enables curcumin to be used in many acid-base demonstrations and incorporate ideas such as hidden messages and mechanochemistry.

The Value of Microtitrations

Microtitrations can be used as a stand-alone lesson or as an introduction to more complex titrations. Done without expensive glassware and materials, this alternative to buret titrations is easy to implement in most classroom situations.

Not so Green Up Close: a Peek at a dyed Chicago River Sample

Light absorbance and fluorescence were studied for a sample of the Chicago River that had been dyed green for St. Patrick’s Day. The sample had weak green fluorescence, showing that the intense green appearance of the river was in part due to the long path length of light through the water. The ability of the green color to partition into 1-octanol was also explored.

Egg-lectrons and McLewis Structures

Egg cartons and beverage holders can be used as models of atoms, with their dimples representing orbitals. Each dimple can hold up to two objects such as milk jug caps, plastic eggs, and cup pieces to represent electrons in the orbitals. Partially overlapping the trays by stacking the dimples represents chemical bonding and produces molecular models resembling Lewis structures. The models can be easily made from materials that can be readily found grocery stores and fast-food restaurants.

Bookend Activities to Highlight Chemistry as the Central Science

General chemistry is often perceived as a gatekeeping course for STEM students, particularly in large-enrollment settings. To enhance student engagement and understanding, this study introduces two "bookend" activities—one at the beginning and one at the end of the semester—designed to connect chemistry concepts with students’ interests and career goals.

The first activity, conducted during the first week, prompts students to explore chemistry subfields and career paths via the American Chemical Society (ACS) website, helping them see chemistry’s relevance to their own aspirations. The second activity, due before the final exam, requires students to analyze a chemistry-related news article, linking course concepts to real-world applications. Both assignments promote active learning, a sense of belonging, and an appreciation for chemistry’s role in various fields.

Implemented in large lecture courses, these activities have been well received, fostering engagement and personal connections to chemistry. This approach offers an adaptable model for integrating real-world relevance into general chemistry curricula, potentially improving student buy-in and academic persistence.