General Chemistry

Expanding on Self-Inflating Balloons: Activities Involving Moles, Gas Laws, and Thermochemistry

Balloons that inflate using carbon dioxide produced from the reaction of citric acid and sodium hydrogen carbonate can be used to demonstrate a number of aspects of chemistry. Gas laws were used with the balloons to illustrate limiting reactants, molar mass of gases, and rockets. The endothermic reaction in the balloon was visualized with an infrared camera, and the Green Chemistry aspects of these balloons were considered.

Food Dyes as Acid-Base Indicators

Natural food dyes are being sold online and in stores that can be used as acid-base indicators. These dyes open up a host of possibilities for at-home and in-class. For example, these food dyes can be used as indicators in the quantitative titration of the Mg(OH)2 in milk of magnesia.

Lithium Battery Flame

Inspired by a recent article in the Journal of Chemical Education, Tom Kuntzleman attempted to extract lithium from a coin battery, and to use the extracted lithium to produce a pink flame.

Effect of Temperature on Chemical Equilibrium using Copper Complexes

This post describes a simple way to generate blue, green, orange, and yellow copper complexes, and to use these complexes to introduce students to the effect of temperature on chemical equilibria. The protcol avoids the use of caustic agents, allowing the experiments to be conducted by students as a laboratory-based investigation.

A Multi-Colored Equilibrium Experiment

Solutions of copper (II) dissolved in acetone are easy to prepare, and can display orange, yellow, green, and blue color depending upon conditions. Such solutions allow for a variety of demonstrations and experiments that illustrate principles of chemical equilibrium.