Demonstrations

So You Think You Can Demo

So You Think You Can Demo

“So You Think You Can Demo” is a fun and educational contest sponsored by ChemEd committee members to allow chemical educators to have a platform to share their best hands-on science demonstrations. We encourage all ChemEd 2015 attendees to submit a video showing off your most creative, informative and interesting chemistry demo. The deadline for submission of a demo video is April 30th.

How Does an Orange Peel Pop a Balloon? Chemistry, of Course!

The juice from an orange peel causes a balloon to pop.  When I first saw this effect I immediately thought to myself, “what is the chemistry involved in this experiment?” After quickly searching the web, I found several claims that a compound in orange peels called limonene (Figure 1) is responsible for this effect.  Limonene is a hydrocarbon, which means that molecules of limonene are composed of only carbon and hydrogen atoms.  Limonene is responsible for the wonderful smell of oranges, and it is a liquid at room temperature.

Demonstrating the Colors of Transition Metal Complex Ions

Just the other day within my IB Chemistry HL classes, we were discussing the color of transition metal complex ions in solution. It's a bit imperfect, because they are not yet dissolved, but I set up a number of metal chloride salts in order to help students see the pattern. They are arranged according to the position of the metal in the periodic table. It ends up being quite obvious to the students that the only metal salts with color are in the d-block. I'm now in the process of ordering more chloride salts so I can complete the pattern even more the next time I teach this topic.

 

Chemical Mystery #4: The Case of the Misbehaving Balloon

Conducting experiments with liquid nitrogen experiments is a sure-fire way to energize many chemistry lessons. Unfortunately, getting access to liquid nitrogen can be a bit difficult. I happen to purchase liquid nitrogen from Airgas; you might be able to find a branch near you here.