Modifications are presented for the iodine clock reaction to introduce the concept of activity and to help students better appreciate molecular aspects of chemical equilibrium. The addition of an unreactive salt affects the activity of the reactants in the iodine clock reaction. The difference in activity affects how long the iodine clock reaction…

A mixture of salt water and isopropyl alcohol is immiscible, forming two separate liquids with the organic layer on top and aqueous layer on bottom. When universal indicator is added to such a mixture, all of the indicator compounds in the universal indicator preferentially dissolve in the alcohol--except for phenolphthalein at high pH. Mixtures…

3D printers have facilitated a wealth of 3D printed molecular models illustrating key structural concepts for student learning. However, general adoption of 3D printed models in the organic chemistry classroom proceeds slowly as the majority of consumer-grade 3D (fused deposition modeling (FDM) and resin) printers are inherently monochromatic,…

Describes how the color of an object is related to its chemical structure. (CP)

Investigated use of overhead transparencies containing a sequence of diagrams to represent a three-dimensional structure at different stages during a rotation. Significant learning occurred among 120 Bahraini boys (aged 15-16) when the transparencies contained multi-colored diagrams which were exposed simultaneously or individually in a cumulative…