Observe both an exothermic and an endothermic reaction/process as I use a modified propane torch in the video demonstration.
The solution to Chemical Mystery #13: Bye Bye Blue! is presented. This experiment is useful to demonstrate to students when discussing acid-base indicators, neutralization reactions, or the acidity of carbon dioxide when it dissolves in water.
A simple, but tricky experiment is displayed. Can you figure out how the trick was done?
Based upon reader comments on previously published, Chemical Mystery #12, I experimented and found that this demonstration is easy to pull off with relatively inexpensive and easy to find materials.
Check out the solution to Chemical Mystery #12: Baffling Balloons
Can you explain what is happening in Chemical Mystery #12?
Relevant Topics for Instruction and Assessment
The August 2018 issue of the Journal of Chemical Education is now available online to subscribers. Topics featured in this issue include: the chemistry of candy and sugar, examining virtual learning for laboratories, strengthening student understanding of acid-base chemistry, building scientific communication skills, emphasizing learning, sustainability and green chemistry, cost-effective resources and techniques, laboratory investigations, ConfChem conference on mathematics in undergraduate chemistry instruction, erupting from the archive: soda geysers.
A favorite demonstration is to boil water by lowering the pressure in a bell jar using a vacuum pump. Unfortunately, purchasing a bell jar, vacuum plate, and vacuum pump can run upwards of $1,000 which poses a hardship for many teachers. Here are two simple and inexpensive demonstrations of phase equilibrium and vapor pressure.
Setup: 5 minutes
Execution: 5 minutes to 30 minutes depending on level of inquiry
Innovation and Scholarship
The July 2018 issue of the Journal of Chemical Education is now available online to subscribers. Topics featured in this issue include: connecting art and energy, solar cells, examining organic chemistry students’ understandings, computer-based learning, molecular symmetry and visualization, inquiry-based learning, safety management, biochemistry, watching the archive: chemistry goes to the movies.
Technological Pedagogical Content Knowledge (TPCK) can be the vehicle by which teachers decide if and how a technological application can be incorporated into their classrooms. TPCK more recently coined as TPACK technology, pedagogy and content knowledge incorporates technology into Lee Shulman’s pedagogical content knowledge (PCK) construct. PCK is the means by which a teacher takes his/her content knowledge and transforms it into content knowledge for his/her students.