Demonstrations

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.

 

A Chemist Celebrates the International Year of Light

 

Happy New Year!  Did you know that 2015 is the International Year of Light (IYL)? IYL is a “global initiative adopted by the United Nations to raise awareness of how optical technologies promote sustainable development and provide solutions to worldwide challenges in energy, education, agriculture, communications and health1”.  IYL is sponsored by several organizations with interests in science and science education, including the European Physical Society, the Institute of Physics, the American Physical Society, and the American Institute of Physics.  You can find several lesson plans, videos and other educational resources on the IYL website2. 

Chemistry At the Mall

My local chapter of the American Chemical Society sponsors an annual event at a local mall called “Chemistry at the Mall”. The event is in celebration of National Chemistry Week. This year’s theme is “The Sweet Side of Chemistry – Candy”. I advise an ACS ChemClub and we hosted a table at “Chemistry at the Mall”. Ten student members worked shifts from 11am – 4pm. This was a great way to get involved with my local chapter and meet some other members. My students had a great time providing outreach and introducing young children to chemistry.