high school

Burning paper towels soaked in various metal nitrates

Igniting paper towels that have been soaked in concentrated potassium nitrate and allowed to dry yields a flame reminiscent of that produced by guncotton. Repeating this experiment with other metal nitrates produces flames with different colors, plus a few other chemical surprises! This series of experiments is fascinating and connects to a wide variety of chemical topics including combustion, redox reactions, chemical thermodynamics, and flame tests. You don't want to miss this one!

My Modified Grading Strategy

Anthony Stetzenmeyer's grading strategy provides an alternative option to offering required retakes on summative assessments. It has the added bonus of helping his AP chemistry students prepare for the AP exam while learning to cut their losses.

Unit Cells and Layer Sequences using Dimpled Packaging

Regularly dimpled trays such as those used in food packaging can be used to represent layers of atoms in solid structures. For example, the square array of dimples in transparent plastic mini quiche trays can be used to depict layers within cubic or tetragonal unit cells. Multiple solid structures and ways to represent those structures are described.