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.
Have you seen the rainbow candy experiment? It's a very simple experiment that involves pouring water into a plate that has M&M's candies or Skittles arranged in a pattern. Very curious shapes of sharply divided regions form spontaneously. How does this happen?!
In this activity, students learn about solubility and concentration. They watch videos that explain the dissolving process, how to calculate the molarity, supersaturation and how to make rock candy. They also use a PhET simulation to explore factors that affect the concentration of a solution.
The Devil's Milkshake is a simple, yet interesting chemistry experiment that fits well as a Halloween demo.
Erica Jacobsen shares highlights from the September 2019 issue of the Journal of Chemical Education of special interest to our ChemEd X community.
The solution to "Chemical Mystery #16: A Red, White, and Blue Chemistry Trick for You!" is presented. How this experiment can be used as a springboard to carry out a simple quantitative analysis of salt solubility is also discussed.
Watch this video and see if you can figure out how red, white, and blue colors can all be made from the same chemical solution!
Density Bottles can be used to teach a variety of chemical concepts such as density, solubility, and polarity. In this post it is shown that Density Bottles can also be used to differentiate between heterogeneous and homogeneous mixtures, and to explore light scattering.
I think this experiment provides a fantastic vehicle to involve students of all ages in small, hands-on and exploratory research projects. Like many others, my students and I have investigated various aspects of this interesting fountain.
Are you familiar with the dynamic density bottle experiment? This interesting experiment was invented by Lynn Higgins, and is sold by various science supply companies. Two immiscible liquids (usually salt water and isopropyl alcohol) and two different types of plastic pieces are contained within a dynamic density bottle. The plastic pieces display curious floating and sinking behavior when the bottle is shaken.