The “Elephant Toothpaste” experiment is a very popular, albeit messy chemistry demonstration. To carry out this experiment, place a 250 mL graduated cylinder on something that you wouldn’t mind getting messy. Next, add 75 – 100 mL of 30% hyd
elementary school science
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.
Last year I came across a link on Twitter regarding an art installation by Roger Hiorns in England titled “Seizure.” Some of you may have seen it too – a condemned flat in London was essentially sealed off and filled with more than 75,000 L of supersaturated copper sulfate solution.
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.
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.
Happy December ChemEdX community! On December 2, 2014 I attended the second of three workshops on NGSS (Next Generation Science Standards) through our local ISD (in Kalamazoo County it is known as KRESA).
You’ve heard the old saying, “A picture is worth a thousand words.” How many words for a smell? A single whiff of a familiar scent can whisk me back into the past. Wash my hands with Dove soap—I find myself standing in my grandmother’s house. Walk by someone wearing Eternity cologne—I’m back in high school with an old boyfriend. Spray out a foamy mound of Barbasol shaving cream—I’m standing at an exhibit booth talking about the Journal of Chemical Education (JCE). That was a fragrant flashback moment I had last month. As I followed my nose to the past, it led me to a solution for the present.
Congratulations to Grazyna Zreda who solved the Chemical Mystery of the Mentos candies! To conduct this trick, two white Mentos candies are placed in separate beakers that both contain universal indicator. One of the Mentos candies turns the indicator slightly green, indicating the presence of base.
On September 2, the American Association of Chemistry Teachers (AACT) launched its official website, loaded with lots of resources and member benefits. If you visit teachchemistry.org, you will find many great tools that K–12 teachers of chemistry can use in their classrooms; the new online periodical, Chemistry Solutions; professional development opportunities; and a community for you, in addition to many other benefits.