Combustion—The fact that the fuels discussed in the article undergo combustion makes that a good topic for classroom discussion. If you cover combustion as part of a unit on types of chemical reactions, that would be a good time to have students read this article.
Hydrocarbon fuels—Because petroleum and natural gas are currently hot topics, in part because of their rising prices and partly because of the on-going political debate about “dependence on foreign oil,” students should understand that these chemical substances make up fossil fuels.
Organic chemistry—If your curriculum includes organic compounds, you can also use the article as an example of the importance of many organic compounds.
Alloys—Alloys are mentioned only briefly in the article. This may be a topic you would want to expand on with your students. See the Websites section below for a resource on alloys.
Technology—Students may not understand the difference between science and technology since the two terms appear together so frequently. The design and production of the 2008 Olympic torch provides a good example. By applying what science knows about alloys and combustion, for example, to the design and production of an effective Olympic torch, technology can apply the concepts of science for a useful purpose.
Possible Student Misconceptions
“Combustion can only take place in the presence of oxygen in the air.”The article mentions the fact that combustion takes place in space where there is no atmospheric oxygen. The combustion reaction in these situations relies on a chemical called an oxidizer (or oxidizing agent) to supply the oxygen for combustion. For more background on this see the last few paragraphs of More on the Olympic torch and flame.
“The Olympic flame is kept lighted continuously after it is first lighted in Greece.”Technically that’s true, but many of the individual relay torches go out along the relay route. The article mentions several lanterns that are each lighted from the original flame in Greece. They represent the original flame and if any of the torches are extinguished by accident, weather or protester, the torch is re-lighted by one of the lanterns.
Demonstrations and Lessons
You can have students compare fuels in a lab activity like this one. Since the article is about different fuels used in the torches, this might be an interesting activity.
The article says that many of the experts who help design the torch and flame are pyrotechnic experts. Among their areas of expertise is making fireworks. You can have students make sparklers using a procedure similar to this one: http://chemistry.about.com/od/demonstrationsexperiments/ht/sparkler.htm. These need to be handled with extreme caution.
For a NASA unit on combustion see http://astroventure.arc.nasa.gov/teachers/pdf/AV-Atmoslesson-5.pdf. You may already have combustion labs in your course’s lab manual. Students can test for the products of combustion using limewater and cobalt chloride paper, etc.
Another lab activity could be a more standard chemistry lab on the flame colors of metal ions similar to this one: http://www.kent.k12.wa.us/staff/carriewattles/chemistry/flametestlab_inst.htm; or you can show these videos: http://jchemed.chem.wisc.edu/jcesoft/cca/cca2/MAIN/FLAME/CD2R1.HTM.
Student Projects
You can assign small groups of students (or individual students) one of the summer Olympic games and have them research the torch and flame for those games.
Have each student read the three articles in this edition of ChemMatters that relate to the Olympics and discuss the ways in which chemistry is important for the Olympics.
Assign teams of students to design an Olympic torch according to the specifications given in this Teachers Guide (See More on Olympic torch and flame) and also make a prototype of their torch.
Anticipating Student Questions
“Why would keeping the torch burning on Mt. Everest be a problem?”Although the percent of oxygen in the atmosphere remains at about 21% regardless of altitude, the TOTAL amount of oxygen decreases as you rise in elevation. At 29,000 feet (about the height of Mt. Everest) there is about five times less oxygen present, making combustion more difficult. For a somewhat different view, see http://www.npr.org/templates/story/story.php?storyId=11331007.
“I’m not sure what an oxidizer is.”For an answer to this see the last few paragraphs of More on the Olympic torch and flame.
“The article talks about a liquid fuel. Do liquids burn?”Liquids do not burn. In general liquids we think of as fuels are conveniently stored as liquids, but in order to burn, the liquid vaporizes and the vapor then combines with oxygen to burn.
More sites onthe Olympic Games The official web site of the International Olympic Games is http://www.olympic.org/uk/games/index_uk.asp. It includes much more information about the Olympic torch and flame.
More sites onthe Olympic Torch The Olympic Museum publishes a history of the Olympic Torch, which you can read here: http://multimedia.olympic.org/pdf/en_report_655.pdf.
More sites onOxidizers For a more complete description and listing of oxidizers, see http://safety.science.tamu.edu/oxidizers.html.
To read a Chemical and Engineering News article on pyrotechnics, which includes discussion of oxidizers, see http://pubs.acs.org/cen/coverstory/86/8626cover.html.
More sites on Extreme Conditions To read an online article from National Geographic about the Olympic flame, featuring an interview with ACS staff person Jerry Bell, see http://news.nationalgeographic.com/news/2008/04/080409-olympic-torch.html.
More sites on Alloys For an extensive table of alloys and their composition, see http://www.csudh.edu/oliver/chemdata/alloys.htm
