Penney Sconzo presented this nifty demonstration at the ChemEd 2015 Generations Symposium in Kennesaw State University, Kennesaw GA. This is an easy, colorful and safe microscale version of the Ammonia Fountain.
Citric acid is a user-friendly, inexpensive, water-soluble, crystalline solid carboxylic acid. In comparison to using hydro-chloric acid solutions, using solid citric acid and its solutions in water is safer and more convenient. For inexperienced students its titrations against strong base are easier to perform.
Your students may find it interesting to determine and compare the acid content of individual sour hard candies. In addition to doing the titration analysis and the calculations, reported as the percent by mass of citric acid, students can learn about the technology of candy making.
Your students may find it interesting to compare the acid content of a low-acid apple juice or a low-acid orange juice to that in a regular juice of the same brand. These sample types could be added to an existing acid-base titration experiment, form the basis of a new experiment, or be used as project topics.
The Poly Density Bottle1 is a fascinating demonstration primarily due to the phenomena being counterintuitive to what one would expect. The bottle containing white and blue beads suspended in a clear and colorless liquid is shaken vigorously, distributing the beads randomly throughout.
In this article two example applications of gravimetric titration — acid content of fruit juices/soft drinks and pH titration curves — are presented. Both are suitable for laboratory experiments in senior secondary school chemistry courses or in college general chemistry courses.
As part of the grade 12 equilibrium unit, I have my students perform a very traditional lab activity demonstrating Le Châtelier's principle. They rotate through a series of stations where they use a semi-microlab approach to investigate a different equilibrium system at each one.