Chemistry Environment and Pollution As Viewed by Students and Teachers A. Siiade, M. Begel, M. ~hastretle: D. Cms, and G. Jourdan Laboratoire de Recherche en Didactique des Sciences, Case 16, Universitb de Montpellier I I , Place Eugene Bataillon, 34095 Montpellier Cedex, France The results of a study on the "perception of the environment" by middle school students have been published ( I 2) or are eurrrently under publication (3).Our focus is now to elaborate the teaching modules taking into account the results that we have already obtained. However, it also seemed interesting to report on the perceptions on the connections between chemistry and pollution by the following groups: 10th and l l t h gradeZ high school students and third-year undergraduate students in chemistry, and fourth-year undergraduate students in a college of pharmacy. Thus, we hope to measure the part of the knowledge that has been acquired through actual study of scientific concepts and that which is common knowledge. It also seemed useful to interview the chemistry teacherslprofessors before making concrete propositions that will enable us to remove by our teaching the ambiguity of the difference between acquired and common knowledge. Methodology In the first step, nondirective interviews were conducted with about 50 students in order to define the key concepts related to the environment. Aquestionnaire was then constructed and tested under different versions culminating in a final version. For the question concerning whether chemistw creates andlor solves problems of pollution, two differentarrangements were adopted corres~ndingto two different versions. "A" and "R". This questionnaire was given to:
Levels 0
TIP
Ph
PS
J
S
F~g~re 1. F = Food. A = Arms, C = Commun~cat~on. CP = computers, rl = Health, S = SporIs.T = Transportallon Importance glven lo cnemIstry in o~fierentdomams accord ng to tne o fferentcategorfesof respondents Domains for Which Chemistry Is Rated as lmportanl The following scores were reported: HEALTH (3.3.-3.91, ARMS (3.0-3.5.). and FOOD (3.0-3.4). For these domains the sc&e increaks with the st'udents'&es. In addition it is noted that the rate of "non res~onses"isverv low (less than 1%) as well as the rate of "don't know" respkses (less than 5%). In contrast to the students, the teacherdprofessors give in every domain an average score as shown in Table 2.
64 (10th grade high school students)(S)
59(11th grado high who01 ~tudcnt~cscientifir option tJ). 32 third-vear undermaduate ~hvsiral science students IPS). . .
47 fourth-yearundergraduate students at the College of Phar44
macy (Ph). High school teachers and college professors of chemistry (TIP).
Therefore, there was a total of 246 responses, but the different types of respondents were analyzed separately. For each question average scores were calculated assigning a score of "4" for the response "very important", "3" for "important", . . .; therefore, the maximum score is 4. Importance Given to Chemistry in Different Domains The average scores obtained in every domain for each category of respondents. (Table 1)were used to construct Figure 1. Note again that four is the maximum score in each domain. ..~~--.------The profile of responses clearly indicates two types of domains (cf.Table 1). ~
'current address: LIRDIS, Universite de Lyon 1, 43 bd du 11 Novembre 1918,69611.Villeu*anne, France. '10th grade corresponds to "secondenand llth grade corresponds to "premibre"in the French high school system.
Domains for Which the Importance of Chemistry Is Rated
as Moderate
"Transportation" and "Sports" have scores slightly higher than 2 for students. "Computers" and "Communication" have scores even lower than 2 for the same groups. It is noted that the students'ages have little impact on these scores. Table 1. Average Scores Indicating the Importance Given to Chemistry According to the Level of the Respondents Levels
S
J
PS
Ph
3.0 3.0 1.8
3.1 3.2 1.5
3.4
2.0
1.7
3.3 2.1 2.5
3.6 2.3 2.0
3.3 3.5 1.6 1.6 3.7 2.4 2.5
TIP
Domains Food Arms Communication Computers Health sport Trans~ortation
3.5 1.6 1.9 3.9 2.4 2.2
Volume 71 Number 7 July 1994
573
Table 2. Average Scores lndicating the lmportance Given to Chemistry According to the Level of the Respondents
Domains
Average Swre Given by the Students
Health Food Arms
Average Score Difference behnreen Given by the Teachers/Professors Teachers/ and Students Professors
3.5 3.2 3.3
+ 0.3 + 0.5 + 0.2
3.9 3.7 3.5
However, the teacherslprofessors integrate in a more subtle way the impact of chemistry on the domains that are not considered to be usual fields of application. Again we find a positive difference for the teacherslprofessors. There is a greater difference in the scores here (more than twofold) than in the above section (an average of +0.77 versus +0.33). This is clearly seen in Table 3. Table 3. Average Scores lndicating the Importance Given to Chemistw According to the Level of the ~espondenk
Domains
Transportation Sports Computers Communication
Difference Average Score Average Score between Given by the Given the Students Teachers1 Teachers1 Professors Professors and Students 2.3 2.3 1.8 1.6
3.1
+ 0.8
2.9
+ 0.6
2.6 2.5
+ 0.8 + 0.9
Opinions on the Role of Chemistry in the Domains of "Food" and "Sports"
The domain "Food" belongs to the first type of responses and "Sports" to the second. With this question we wanted to obtain more precise informations on the opinions of the respondents wncerning these two domains. Role of Chemistry in "Food" Table 4 summarizes the results obtained. There were a total of 237 different words quoted to relate chemistry to "Food" with an average of 1.6 citations per respondent. There is a clear distinction here between the scores of high school students (1.2-1.31, and College of Pharmacy students and teacherdpmfessors (2.0, 2.1, and 2.2). Thus, the number and variety of words quoted increase with the students' ages. Moreover, although the scores of College of Pharmacy students in physics and those of the undergraduate students in pharmacy are close, we notice a smaller variety of answers for the former. The most common form quotedis health food (23%),then food coloring (20%). food preservatives (19%), chemical pmducts-fertilizer, toxic chemicals, yeast, pesticides, . . . (12%), and chemical additives (7%). Therefore, college of pharmacy students and teacherdpmfesson have a much better knowledge of applications of chemistry in food than the high school students. However, the number of words quoted is limited to two in the best case and is, doubtless, related more to exposure to concepts through the media than to actual acquired knowledge through studying scientific subjects. 574
Journal of Chemical Education
Table 4. The Role of Chemistry in "Food": Total of Different Ways Cited according to the Level of the Respondents
Level
1Mh 11th Chemistry Pharmacy Teachers/ Professors
Position
Total
Non- Citlrespond responses ent
33
9
0
42
35
39
13
2
26
21
39 38
33 35
7 15
54 54 87 86
43 26 43
19
1.2 1.26
2.08 2.02 2.15
40
Role of Chemistry in "Sports" Table 5 summarizes the results obtained. The number of examples quoted is low in agreement with the rather weak importance given to chemistry in sports (1.0 for high school, 1.3 for college of pharmacy students in physical science, and 1.6 for pharmacy students). Thus, the distinction between high school students and pharmacy students is seen again but not as clearly as with the results in the food domain. Here again teachers/professors have better knowledge than their students, but the number of examples cited per respondent only reaches 1.8. Also, we find a smaller variety of responses than in the case of food. For the students "drug abuse" is the top response (46%), followed by "health" (33%),and "material" used in "sports" (13%). Comments
It is tempting to think that the importance given to chemistry in a particular domain is related to the number of applications in everyday life that quickly come to mind. This is well confirmed when one compares the responses to the questions about food and sports. However, it is clear that the number of applications quoted is limited even in the most favorable cases. The teacherdpmfessors who themselves over-evaluate the importance of chemistry (which would be expected because this is their field), do not quote many more applications than their students. Of course, this raises the question of the relationship between the teaching of chemistry and everyday life. Thus, it is urgent to make the teacherslprofessors aware of this problem, for instance by putting a t their disposal, in the Table 5. The Role of Chemistty in "Sports": Number of Responses according to the Level of the Respondents
Level
Position 1
1Mh 11th Chemistry Pharmacy Students together Teacherd Professors
Total
2
NonCiV responses respondent
3
15 18
4
0
19
19
5
1
24
24
16 20
7 7
2
25 28
19
1
69
23
4
96
79
1O . 1O . 1.32 1.65 1.21
29
22
8
59
32
1.84
17
classroom, documents describing these kinds of applications and also hy integrating them intn the curriculum. The Relationship between Chemistry and Pollution It was expected that chemistry would be perceived more as a source of pollution than as a solution to pollution pmblems. However, in order to take into account a possible influence in the order of the two sub-questions, two forms were used: "creates problems" followed by "solves problems" in version A and in the opposite order in version B. In version A, scores that were obtained with a maximum of " 4 are noticeably homogenous (3.3 to 3.7 for creation of problems and 2.6 to 2.9 for their solution). Furthermore, inversion of the order of questions had little impact since 3.4 to 3.8 is obtained for "creates" and 2.2 to 3.3 for "solves". In both cases the rate of nonresponses reaches 50% for the two questions. The variation between the two questions is, therefore, important whatever the order of the questions. This variation corresponds to an unfavorable image of chemistry. Only the chemistry teacherdpmfessors have a more balanced view with a score of 3.6 for "creates" and 3.5 for "so1ves"inversion A, as opposed to 3.5 for "creates" and 3.6 for "solves" in version B. However, care should be taken in interpreting these results because of the high rate of nonresponses. This fact alone provides a good measure of the work that will be necessary for the chemistry teachers/pmfessors concerning the preconceived ideas of their students. Water Pollution Origin
Four sources of water pollution were given to the respondents: agriculture, individuals, industry, cities; and they were also given the opportunity to indicate other examples: Only 10% of the respondents took this opportunity. The teacherslprofessors cited 25% of other sources. Table 6 and Figure 2 summarize the responses. Industry is considered as the main source of pollutionclearly more important than others at every level. Thus, we find again what we already saw with middle school students. On the other hand, with the 10th grade high school students, agriculture receives a weak score (like in middle school) and reaches the level of other sources only aRer that. The teacherdprofessors have a more balanced view and favors industry only slightly Examples of Pollutants
We expected that the high school students, the College of Pharmacy students, and the teacherdprofessors, would precisely identify according to them, what are the pollutTable 6. Average Scores Obtained for Different Origins of Water Pollution Origin
Agriculture Individuals Industry Cities
Figure 2. I = industry, Ind = Individuals, C = Cities, A = Agriculture. Sources of water pollution amrding to the level of the respondents. ants of water by relating them to their origin. The results are indicated in Table 7. The importance given to industry as a source of water pollution is seen by the higher number of examples given than for the other sources, although only slightly, since there is only an average of 0.9 examples per person. It is also noted that the teacherslprofessors (in chemistry and in physical science) name only 0.86 examples per person that may be due to a more optimistic point of view or, more likely, to relative unfamiliarity. Agriculture is appreciated diversely by the high school students (0.8 examples per person), by the College of Pharmacy students (0.95 examples per person, which was higher than for industry). The source "individuals" is perceived more homogeneously except for the teacherdprofessors and the 11th graders who in their estimation thought that it was less important than the other categories. "Cities" receive only 0.70 citations per person and here again the teachedprofessors quote fewer examples than for the other categories. Acid Rain Origin
Table 8 and Figure 3 show the obtained results. Chemical industry also receives high scores (3.5 and 3.7) that are homogeneous according to the levels with only a slight shift toward the lower score for the teacherdpmfessors. Transportation is much less perceived as a source of acid rain except by the teacherslprofessors and the college chemistry students who accorded scores close to that of industry. The score accorded to "means of heating" is even lower except for the teacherdprofessors who are here the only ones to recognize their influence. Substances Responsible for the Acidiiy
Level 10th
2.5
3.3
3.8
3.3
11th
3.1
3.2
3.8
3.5
Chemistry
3.1
3.3
3.8
3.2
Pharmacy
3.2
3.3
3.9
3.4
Teachers/ Professors
3.5
3.4
3.6
3.2
Contrarv to what could be exuected from the odnions on the orifin; of acid rain, the substances rrsponsihle fur the acidity of rain are still not well known (Table 9,. Of the high school and College of Pharmacy chemistry students interviewed. three auarters of them are unable to indicate a single substance; whereas, they attribute an imDortanc role to chemical industw in acid rain. The Colleee bf Pharmacy and the teachersldrofessors do better, but i n the average they quote only,oneexample. Volume 71 Number 7 July 1994
575
Table 7. Number of Examples Cited According to the Level of the Respondents and the Sources of Water Pollution
Level
Examples
Total Citations
Nonresponses
Citations/ responses
Agriculture S
25
1
26
30
0.87
J
32
3
35
45
0.78
PS Ph
20
4
24
26
0.92
24
11
35
37
0.95
TIP
21
9
30
37
0.81
Individuals S
41
2
43
54
0.80
J
31
2
33
50
0.66
PS
24
3
27
28
0.96
Ph
24
11
35
40
0.87
TIP
18
4
22
35
0.63
lndustry S
58
0
58
63
0.92
J
44
7
51
58
0.88
PS
29
0
29
32
0.91
Ph
40
4
44
47
0.94
TIP
27
2
29
38
0.86
52
0.69
Cities S
36
J
PS
0
36
32
2
34
53
0.64
19
0
19
28
0.68
Ph
23
3
26
39
0.67
TIP
16
1
17
33
0.52
Sulfur-based pollutants that quickly come to mind concerning air pollution are quoted, all categories t o g e t h e r 4 times including 25 by the teacherdprofessors and 17 by the pharmaey students. The substances most often quoted are sulfur dioxide SOz (28 times) and sulfuric acid (12 times). Therefore, it is clearly apparent the most important air pollutants are not known by some high school and university students. Nitrogen-based pollutants, essentially nitric oxides (NO,), are auoted for a total of 38 times including 22 times by tk tea~herd~rofessors and nine times by theiharmacy students. Carbon-based pollutants were auoted 24 timesincluding 18 times just ~0~ that was 14 times by the teacherdpmfessors and the pharmacy students. "Non18 times, but the small chemical" pohutants were number and the scattering .of responses did not permit a detailed study. Discussion
These results reveal the pwr knowledge of people presumed to be scientificallyaware of the sources of acid rain. 576
Journal of Chemical Education
Figure 3.C1= Industry, T = Transportation, H = Health. Originsof acid rain according to the level of the respondents. Media coverage of this serious problem allows, even these particular neo~le to attribute some res~onsibilitvfor ~ o l l u tion to cekaain'human activities but does not h;lp tcemto understand the mechanisms and evenless howto diminish pollution. Conclusion In our society, the role of chemistry is perceived negatively because the media focuses so much on the polluting and even harmful role of chemical industry. The high school and university students actually see it this way. h d u & is considered as being polluting. Chemistry creates more ~ollutionproblems than it solves. It is the most responsible for wa& pollution and acid rain. We expected that university physical science or pharmacy students would have a more balanced view. Indeed we see that. but this is still weak es~eciallvfor the university students in physical science. The teacherd~mfessorshave a more balanced view that is, nevertheless: the minimum expected. The frequent linking of "natural", "good", and "pure", on one hand and "chemical", "dangerous", and "impure" on the other hand, is obvious ("drug abuse," for instance is the main application of chemistry in sports!). Thus, particularly for the youngest group, "agriculture" keeps a positive A
Table 8. Average Scores (out of four) Obtained for Different Origins of Acid Rain
Source
Chemical lndustry
Transportation
Heating
Levels 10th
3.6
3.0
2.0
11th
3.6
2.9
2.0
Chemistry
3.5
3.4
2.3
Pharmacy
3.7
3.0
2.1
Teachers/ Professors
3.4
3.3
3.3
Table 9. Number of Substances Cites as Responsible for the Acidity of Rain according to the Level of the Respondents
Example None
1
2
30r4
Total Citations
Level 1Mh
49
10
3
2
15
11th
44
12
2
1
15
Chemistry
24
4
3
1
8
Pharmacy
21
10
12
4
26
Teachers1 Professors
8
19
11
6
36
image (probably related to the very bucolic image of the country and its immediate utility for nourishment) as opposed to industry and cities. The older students and adults counterbalance this view by integrating the negative aspects of the image of agriculture associated with the chemistry of fertilizers and with its industrialization. What is remarkable, even worrisome, for the teaching of physical science, is that the negative aspects of chemistry,
indeed, rely most often only on impressions, because a large number of respondents perceiving chemistry as a source of pol%of non Responses lution are unable to mention at least one polluting substance. It would be appropriate that the curriculua present a more 0.25 77 balanced view of t h e role of 0.25 75 chemistry in our society. For that, the teachers should first be 0.25 75 correctly informed on the pradical applications of the sub0.55 45 stances to be studied. In addi0.82 18 tion, they should explore the problems posed by these substances, and their impact on the environment as well as ways to solve these problems. This, of course, implies relevant information and documentation, and in this aspect cwperation between teaching and industry seems indispensable. Literature Cited 1. Jourdan 0.; C m D.: Sivade A. B. P 1992, 743,595-600. M.: Cros D.: Chastrctte M., In Act- Eeole d'automne 7.8 G m d e
2. Sivade A,; Bpgel
Motte',Bullefin du CIFEC:MrmtpelPer, 1991; p 158. 3. Sivade A ; Begel M.: Cms D.: Jourdan G., submitted for publieationin Amdomio.
Volume 71 Number 7 July 1994
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