high school chemistry

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.

Using Periodic Properties to Group Students for an Activity

Today in my IB Chemistry class we were reviewing the Born-Haber cycle. This has proven particularly challenging in the past so I wanted to try something a bit different and have the students review in groups. The task for each group of students was to create a visual Born-Haber cycle for potassium oxide - ignoring the math and calculations but instead focusing on each process within the cycle. I'd like to share how I grouped students using periodic properties.

Why do we have to do chemical equations and calculations?

Fe & Sulfur reaction

(A look at workplace exposure limits found in MSDS sheets)

There is useful information in section 8 of a (Material) Safety Data Sheet (MSDS) that teachers can use and shows how a knowledge of chemical equations and calculations helps protect the health of their students and themselves and helps to assure their employers and safety officers that teachers and lecturers are responsible and professional users of chemicals. 

Opportunities For Chemistry Modeling Training

modeling training

The Modeling™ curriculum emphasizes modeling, collecting evidence, scientific discourse and development of conceptual understanding. All of these can be linked to AP and NGSS standards. If you are looking to make improvements in your curriculum and gain some impressive strategies, consider enrolling in a workshop this summer. There are many workshops scheduled around the country during the summer. A full curriculum and support materials are provided.

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.


Hach Grant


I teach AP chemistry and general chemistry at Hudsonville High School in the Grand Rapids area.  I applied for the HACH grant last spring and was very excited when I was one of the recipients that was accepted.  The process of applying is very easy.  Your request obviously has to be well thought out.