Chemical Education Today

www.JCE.DivCHED.org • Vol. 82 No. 2 February 2005 • Journal of Chemical Education 185

Especially for High School Teachersby Erica K. Jacobsen

Classroom Credit

Secondary School Featured Articles

� A Cool Drink! An Introduction to Concentrations, by MindyBedrossian, p 240A—B.

� Fractional Distillation of Air and Other Demonstrations withCondensed Gases, by Maria T. Oliver-Hoyo and WilliamL. Switzer III, p 251.

� The Determination of the Percent of Oxygenin Air Using a Gas Pressure Sensor,by James Gordon and Katherine Chancey,p 286.

“It’s everywhere you want to be.”Readers versed in television jingles may remember the

above phrase from the commercials of a well-known credit cardcompany. While television has connected this familiar taglinewith visions of retail purchases, it recently came to mind as Ireflected on the different ways people use JCE Classroom Ac-tivities. This past fall, my eight year-old niece needed a topicfor a science fair project. My mother was going to be guidingher through the process, and asked mefor possible topics. I suggested the re-cent Activity “A Magnetic Meal”(1). It used the familiar substanceof breakfast cereal to provide asurprising result, had suggestionsfor further investigation, andcould be performed in the home.Did it matter that they didn’thave access to a balance with anaccuracy of 0.001g? Did it mat-ter that she didn’t know how towrite a balanced equation for thereaction of iron with hydrochloric acid? No. The parts of theActivity that were too high a level for her were easily adapted.They didn’t weigh the iron obtained, but showed its presenceon a coffee filter. They omitted the reaction with HCl, butincluded the familiar sight and color of rusted iron. The projectwas a success and even led my niece to seek out a book onvitamins and minerals and read it out loud to my mother, thetwo of them discussing the ideas as they went. With judiciousadaptation, Activities really are everywhere you want to be—classroom or home, and nearly any grade level.

The flexibility of Classroom Activities to cover any themeis another plus. JCE typically offers Activities that match eachyear’s themes for both National Chemistry Week and Chem-ists Celebrate Earth Day. Turn to p 240A–B for this year’s EarthDay Activity, “A Cool Drink! An Introduction to Concentra-tions”. Bedrossian uses the simple items of presweetened pow-dered drink mix (Kool-Aid), water, and disposable cups andspoons to create an Activity that touches on the varied topicsof serial dilution, parts per million, molarity, and air pollution.It has students calculate how much mercury a person may safelyinhale daily, according to the EPA safety levels. It ties in wellwith this year’s Earth Day theme of “Air: Here, There, Every-where”. If I may borrow another credit card tagline: “Kool-Aid: $3. Packages of disposable cups and spoons: $2. Achemistry Activity that can be used immediately to create en-thusiasm for Earth Day 2005: priceless.”

Teachers using the above Activity may also wish to fur-ther extend their discussion of mercury in the environment.In their introduction, Rice et al. (p 265) discuss a site of mas-sive mercury contamination located in the U.S. state of Geor-gia. Industrial tenants released in excess of 400,000 pounds ofelemental mercury into the surrounding salt water estuary over

a period of about 20 years! The authors de-scribe the impact on mercury levels in sea-food. While high school instructors will

probably not use the described lab activity because of the re-quired instrumentation, the data and information it containscertainly provide relevant discussion material.

Foster (p 269) discusses the consequences of broken mer-cury-in-glass thermometers, and her department’s actions tofind accurate and safe thermometers for laboratory use. Stu-dents might be interested in her statement “It has been esti-mated that the cleanup cost of one broken mercurythermometer is about $75–$110 and that the one-half gramof mercury contained in a mercury thermometer is enoughto pollute five million gallons of water.”

One of this month’s Chemical Laboratory Information Pro-files (CLIPs) also presents information about mercury and itshazards (p 203). Why not hand out a copy of this CLIP tostudents? The format is easy to follow and understand, andcan lead to a discussion of acceptable exposure limits of vari-ous chemicals.

ACS Teaching Excellence Endowment

Last month’s issue included an announcement of a newcampaign of the ACS’s Division of Chemical Education. TheDivision is establishing the “Teaching Excellence Endowment”to support awards for high school science teachers in every ACSRegion. Their goal is to raise $300,000, with the first $100,000in contributions to be matched 1:1 by DivCHED. This is anexcellent opportunity to support and reward deserving highschool teachers—those who continually motivate and encour-age students to study chemistry. By the time you read this, I’llhave sent in my own contribution, in honor of my excellenthigh school chemistry teacher (my dad!). Please consider lend-ing your own support.

Literature Cited

1. JCE Editorial Staff. J. Chem. Educ. 2004, 81, 1584A–B.

phot

o by

Loi

s J.

Bode

photo by Mindy Bedrossian