activity

The Write Stuff: Using Paper Chromatography to Separate an Ink Mixture

In this Activity, students perform a variation on the standard paper chromatography separation of black ink. They compare the separation of black ink using four different solvents: water, rubbing alcohol, vinegar, and household ammonia, and then mixtures of the four. It introduces students to methods of selecting the best solvent for a separation and the effects of adding acid and base.

How Many Colors in Your Computer? Discovering the Rules for Making Colors

In this Activity, students investigate the colors displayed on a computer monitor with a magnifying glass. They then mix colors first using light, then using paints or crayons. This Activity could be used in discussions of solid state chemistry when LEDs, phosphors, or liquid crystals are discussed.

New Paper from Newspaper

In this Activity, students examine a piece of newsprint and recycle the paper to make a new sheet of paper that can be compared to other types of paper. They then use this experience, and information from Internet sites, to create a paper work of art. The Activity could be used as a cross-curricular topic in an art class.

Silver to Black - and Back

In this Activity, students remove tarnish from silver using the reaction of tarnish with aluminum. If only untarnished silver items are available, students first tarnish them using items that contain sulfur. This Activity could be used with topics such as chemical changes, metals, electrochemistry, and redox reactions. The Activity could introduce a discussion of silver and its reactions.

What's Gluep? Characterizing a Cross-Linked Polymer

In this Activity, students make a cross-linked polymer called "gluep" using white glue and borax solution. They then investigate its properties, and "un-gluep" and "re-gluep" it using vinegar and baking soda. This Activity can be used in discussions of polymers or properties of liquids and solids. It demonstrates the composition and alternative use of a common household product.

LEDs Are Diodes

In this Activity, students compare incandescent bulbs and LEDs powered by dc and ac voltage sources. They use circuits made from cut-up holiday light strands, with some of the incandescent bulbs replaced with LEDs. The diode nature of LEDs is demonstrated, as well as the energy associated with different wavelengths of light.

Out of Thin Air: Exploring Phase Changes

This Activity illustrates sublimation/deposition with dichlorobenzene (mothballs) and evaporation/condensation with water. This Activity could be used to introduce the phases of matter and phase changes at both the macroscopic and microscopic levels.

CD Light: An Introduction to Spectroscopy

In this Activity, students use a CD to build a simple spectroscope. They use it to investigate how different colors of light interact with colored matter. This qualitative Activity could be used as a general introduction to spectroscopy and the concepts of complementary colors and absorbance.

Tick Tock, a Vitamin C Clock

In this Activity, students make a chemical clock using chemicals found in the supermarket: vitamin C tablets, tincture of iodine (2%), hydrogen peroxide (3%), and liquid laundry starch. They investigate what happens to the speed of the clock when the reactant solutions are made more or less dilute.