Using Product Content Labels To Engage Students in Learning

Mar 31, 2014 - This communication describes an activity to encourage learning chemistry nomenclature in which students use cameras (including readily ...
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Using Product Content Labels To Engage Students in Learning Chemical Nomenclature M. Araceli Calvo Pascual* Facultad de Formación de Profesorado y Educación, Universidad Autónoma de Madrid, 28049 Madrid, Spain ABSTRACT: This communication describes an activity to encourage learning chemistry nomenclature in which students use cameras (including readily available cellphone cameras) to photograph and then evaluate consumer product content labels, linking classroom knowledge to real-world experience. In addition to learning chemistry nomenclature, students engage in discussions about differentiating actual product contents and the claims made about the product, while connecting how chemistry is in all the products that they consume. KEYWORDS: Elementary/Middle School Science, High School/Introductory Chemistry, First-Year Undergraduate/General, Public Understanding/Outreach, Multimedia-Based Learning, Consumer Chemistry, Nomenclature/Units/Symbols, Student-Centered Learning he activity “Go Chemistry: A Card Game To Help Students Learn Chemical Formulas”1 shows an interesting card game that can be a quite useful resource for secondary school students when chemical nomenclature is first encountered. As the author indicates, there are many chemical formula card games reported in this Journal, but there are also several methods intended for learning chemical nomenclature published in this Journal that I would like to mention. A literary review published since the 1980s describes games such as a Web-based mnemonic game published recently2 and other games published previously,3−8 computer programs,9,10 activities based on flowcharts11 and schemes,12,13 procedures to determine oxoacid formulas,14 mnemonic rules,15 and specific methodologies.16−18 In addition, there are other activities published in this Journal not categorized with the keyword term “Nomenclature/Units/ Symbols”, but which can be used to learn this topic as well, such as the activity described by Pippins et al.19 Because students often have difficulty learning chemical nomenclature, it is important for teachers to use many different methods to improve the teaching of this subject: The more hands-on activities that can be employed to teach nomenclature, the better. Accordingly, an activity to promote learning nomenclature with a camera is suggested. The activity has been tested successfully with first-year undergraduate students but could also be used at the high school level.

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METHOD The teacher introduced the activity to the students on the first day of class and it lasted until the end of the year. In the first class session, the teacher made an assessment of students’ existing chemical nomenclature knowledge and queried their opinions about its importance in their daily lives. After the discussion, the teacher reviewed some common substances, showing a presentation titled Chemical Nomenclature: Some Examples with Common Consumer Products with photographs that showed one or more everyday products (without brands) that contained the substance whose name and formula was being discussed (see Figure 1). Afterward, the teacher instructed students to create their own album by taking photographs of additional products that contained samples elements and compounds. The students were asked to write on the photograph the name and formula of each substance that the product contained. Therefore, students were taking an active part in their own learning process. During the school year, as chemical nomenclature was discussed, the teacher asked students to comment on the photographs they had taken, encouraging students to continue taking photographs and advising them on their work.

OBJECTIVES

The objectives of this activity are to: Stimulate students’ interest in learning chemical nomenclature. Promote mastery of chemical nomenclature through exposure to everyday products. © 2014 American Chemical Society and Division of Chemical Education, Inc.

Make students aware of the importance of chemistry in their lives through products encountered outside the school or college. Encourage students to develop the habit of reading product labels and to evaluate the product contents prior to purchase or use. Discover errors or inaccuracies on labels relating to names, formulas, and abbreviations for units, according to the specifications given by IUPAC.

Published: March 31, 2014 757

dx.doi.org/10.1021/ed300659c | J. Chem. Educ. 2014, 91, 757−759

Journal of Chemical Education

Communication

At the end of the year, the students formed groups of five or six members and shared their albums. They had to categorize the photographs into ions, elements, and compounds (inorganic and organic), which then had to be subclassified by their chemical components. Finally, every group gave a presentation and discussed their findings with the rest of the class.



RESULTS AND DISCUSSION

An analysis of the initial assessment showed that most of the students had a poor knowledge of chemical nomenclature and that they thought that chemical nomenclature was a boring topic that had to be studied in chemistry class but which had no

Figure 1. The label of a bottle of water as an example to study ions (cations and anions).

Table 1. Comparative Student Examples with Substance Identities and Sources Ions

Formula Li+ Ca2+ Cl− SO32− Formula

Cations Anions Elements

Fe I2 N2 Inorganic Compounds Hydrides Oxides

Peroxides Salts

Other Binary Compounds Hydroxides Oxoacids Salts

Acid salts Organic Compounds Hydrocarbons Alcohols Ketones Acids Salts Esters Polymers

Formula NH3 CO2 N2O SiO2 H2O2 NaCl KI KF KCl MgCl2 NaF SiC NaOH H2SO4 HNO3 NaClO CaCO3 NaNO2 KNO3 K3PO4 Ca3(PO4)2 PbCrO4 NaHCO3 NH4HCO3 Formula

CH3−CH2−CH3 CH3−CH2−CH2−CH3 CH3−CH2OH CH3−CHOH−CH3 CH3−CO−CH3 CH3−COOH (C6H5)−COONa CH3−COO−CH3 [(C6H5)−CH−CH2−]n [−CH2−CH2−]n

Name

Product

lithium ion calcium ion chloride sulphite Name

camera digital battery skimmed milk; soy milk low-mineralized water hard cider Product

iron iodine nitrogen

fertilizer stick povidone−iodine thermal water spray

Name

Product

ammonia carbon dioxide dinitrogen oxide silicon dioxide hydrogen peroxide sodium chloride potassium iodide potassium fluoride potassium chloride magnesium chloride sodium fluoride silicon carbide sodium hydroxide sulphuric acid nitric acid sodium hypochlorite calcium carbonate sodium nitrite potassium nitrate potassium phosphate calcium phosphate lead(II) chromate sodium bicarbonate ammonium bicarbonate Name

household ammonia carbonated soft drink whipped cream glass bottle hydrogen peroxide 100% natural sea salt (additive-free); rice drink from organic cultivation iodized sea salt fluoridated sea salt salt low in sodium salt for hypertensive patients toothpaste for sensitive teeth valve grinding paste moisturizer car battery liquid fertilizer bleach chalk cooked ham toothpaste for sensitive teeth isotonic beverage isotonic beverage gloss enamel (yellow) liver salts custard with biscuits Product

propane butane ethanol 2-propanol acetone acetic acid sodium benzoate ethyl acetate PS FCKW-free polyethylene

a gas cylinder a gas cylinder bottle of alcohol 96%; perfume (organic wheat alcohol); alcohol-free beer (1% abv) rubbing alcohol solvent nail polish remover vinegar; sliced bread from organic cultivation mouthwash; shower gel solvent nail polish remover (acetone-free) takeaway package plastic bag; facial exfoliating gel 758

dx.doi.org/10.1021/ed300659c | J. Chem. Educ. 2014, 91, 757−759

Journal of Chemical Education

Communication

Notes

useful applications in their daily lives. Furthermore, they could not give examples of the substances found in products. Although at the beginning of the activity students’ interest in chemical nomenclature was quite low, student interest increased when this topic was studied using photographs of common products that contained the substances discussed. The proposal of creating an album with students’ own photographs was well received by them. Most of the photographs taken by the students showed the label of the product that contained the substance discussed; thus, the students only had to write the formula of the substance corresponding to the name written on the label (except in the case of some labels that stated the formula). Most of the products photographed were food and beverage products, although photographs of other kinds of products were also presented and discussed. Some examples are shown in Table 1. Sharing the photographs allowed students to note that two apparently equal products may have different chemical substances, leading students to appreciate the importance of reading and evaluating a product’s label before buying the product, and that two different products may contain one or more identical chemical substances. The activity also led to discussion on how some advertisements can confuse consumers with phrases such as “this food contains no chemicals”, “calcium of vegetable origin”, and an “alcohol-free beverage” that actually contains alcohol. Students also discovered inaccuracies and errors present in labels according to IUPAC rules,20 such as “N2O” instead of N2O, “SO4Ca” instead of CaSO4, “fluorine (KF)” instead of fluoride, “HCO3” instead of “HCO3−”, “SO4” instead of “SO42−”, “HCL” instead of HCl, “MG/L” or “mg/l” instead of mg/L, and so on. The students considered the activity a fun way of learning chemical nomenclature and seeing how chemistry is in all the products that they consume. Their knowledge of this topic improved significantly.

The authors declare no competing financial interest.



REFERENCES

(1) Morris, T. A. J. Chem. Educ. 2011, 88, 1397−1399. (2) Cossairt, T. J.; Grubbs, W. T. J. Chem. Educ. 2011, 88, 841−842. (3) Chimeno. J. Chem. Educ. 2000, 77, 144. (4) Chimeno, J. S.; Wulfsberg, G. P.; Sanger, M. J.; Melton, T. J. J. Chem. Educ. 2006, 83, 651−654. (5) Crute, T. D. J. Chem. Educ. 2000, 77, 481−482. (6) Russell, J. V. J. Chem. Educ. 1999, 76, 487−488. (7) Mullin, J.; Courtney, P. J. Chem. Educ. 1993, 73, A130. (8) Earl, B. L. J. Chem. Educ. 1991, 68, 1011. (9) Cassen, T. J. Chem. Educ. 1981, 58, 49. (10) Shaw, D. B. J. Chem. Educ. 2003, 80, 711. (11) Robson, D. J. Chem. Educ. 1983, 60, 131. (12) Lind, G. J. Chem. Educ. 1992, 69, 613−614. (13) Rodgers, G. E.; State, H. M.; Bivens, R. L. J. Chem. Educ. 1987, 64, 409−410. (14) Kildahl, N. K. J. Chem. Educ. 1991, 68, 1001. (15) Hawkes, S. J. J. Chem. Educ. 1990, 67, 149. (16) Wirtz, M. C.; Kaufmann, J.; Hawley, G. J. Chem. Educ. 2006, 83, 595−598. (17) Loeffler, P. A. J. Chem. Educ. 1989, 66, 928−930. (18) Martínez, M. M.; Ovejero, P.; Bergondo, E.; Gutiérrez, E. J. Chem. Educ. 1988, 6, 315. (19) Pippins, T.; Anderson, C. M.; Poindexter, E. F.; Sultemeier, S. W.; Schultz, L. D. J. Chem. Educ. 2011, 88, 1112−1115. (20) International Union of Pure and Applied Chemistry: Nomenclature and Terminology (including IUPAC color books). http://www.iupac.org/home/publications/e-resources/nomenclatureand-terminology.html (accessed Mar 2014).



CONCLUSIONS As had been anticipated, the implementation of the camera activity described above allowed both the teacher and the students to accomplish their objectives of learning and relating their daily lives to chemical nomenclature. Therefore, it is fair to state that this activity promoted significant learning of chemical nomenclature. There was every indication that the students would continue relating chemical nomenclature to the reading of consumer product labels in their daily lives. Although the activity was tested with first-year undergraduate students, there is no reason it could not be implemented with secondary school students when they first begin to study chemical nomenclature as well as begin to buy their own food and beverage products. If the teachers agreed, the activity could be continued over subsequent years, when more complex chemistry content is taught. In addition, the students might upload their label photographs onto the secondary school’s Web site or blog for their classmates and families to see. In this way, it would be possible for others to improve their awareness of chemicals in everyday products.



AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. 759

dx.doi.org/10.1021/ed300659c | J. Chem. Educ. 2014, 91, 757−759