hands-on learning

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.

Does Alka-Seltzer Tell the Truth? A lab activity with a video pre-lab assigment

The lab activity shared here is a simple experiment where students use stoichiometric principles to experimentally determine the amount of sodium bicarbonate in an Alka-Seltzer tablet. Novice students tend to find stoichiometric calculations difficult, so practicing the calculations on a pre-lab assignment boosts their confidence and ultimately leads to more successful labs. The Asynchronous Video Pre-Lab Assignment shared here demonstrates the procedure and the calculations required in the experiment.

Thermal Paper as a Polarity and Acidity Detector

Thermal paper such as that used for point of sale receipts typically functions by darkening when exposed to heat. The pigment system used in this paper also darkens when exposed to solvents of intermediate polarity and acids. This enables thermal paper to be used as an inexpensive sort of indicator paper for a variety of demonstrations.

Soda Fountains from Aluminum Cans

The familiar soda fountains that can be produced by adding Mentos candies to plastic bottles of carbonated beverages can also be produced by adding objects to carbonated beverages in aluminum cans. A variety of simple methods for producing soda fountains from cans are described.