Article pubs.acs.org/jchemeduc
When Atoms Want Vicente Talanquer* Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721 United States ABSTRACT: Chemistry students and teachers often explain the chemical reactivity of atoms, molecules, and chemical substances in terms of purposes or needs (e.g., atoms want or need to gain, lose, or share electrons in order to become more stable). These teleological explanations seem to have pedagogical value as they help students understand and use abstract chemical models. They may, however, become a roadblock in developing mechanistic understandings of the structure and properties of chemical systems. I explore the explanatory preferences of college students with different levels of training in chemistry to determine the extent to which they prefer teleological explanations over causal explanations. Major results revealed a strong preference at all the targeted educational levels for explanations that invoke intentionality as a driver for chemical reactivity. I discuss the educational implications of these findings and invite chemistry educators to reflect on these issues. KEYWORDS: General Public, Chemical Education Research, Curriculum, Analogies/Transfer FEATURE: Chemical Education Research
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INTRODUCTION In the common language of many chemistry students and instructors, atoms and molecules are portrayed as very needy things. They take or give away electrons because they “want” to fill their valence shells or satisfy the octet rule. They exchange electrons or ions “in order to” become more stable. They oppose change by any means possible “so that they can return to their preferred” equilibrium states. This way of talking is common not only in chemistry classrooms, but also in chemistry textbooks.1 In my experience, the use of this type of language is a touchy subject for many secondary chemistry teachers and college instructors who become rather defensive when this practice is questioned. For many chemistry educators, anthropomorphizing atoms and molecules and building explanations in terms of wants or needs (teleological explanations) are useful pedagogical strategies for facilitating student understanding of abstract chemical models about the structure and properties of matter at the submicroscopic level. Nevertheless, teleological explanations generate an illusion of understanding that may hinder learning in the longer term. Overreliance on teleological explanations may limit students’ ability and motivation to build deeper mechanistic explanations about chemical phenomena.2,3 It is not my intention in this paper to build a case against the use of teleological explanations in the chemistry classroom. Teachers and instructors at all educational levels rely on a variety of strategies that are known to have pedagogic affordances and limitations.4,5 The main purpose of this paper is to raise awareness about and invite chemistry educators to reflect on this challenging issue in chemistry education. To accomplish this goal, I will first describe results from research in science education, developmental psychology, and cognitive science related to the role of teleological explanations in © XXXX American Chemical Society and Division of Chemical Education, Inc.
people’s reasoning in different contexts. Then, I will describe the main results of a set of exploratory studies designed to investigate the explanatory preferences of college students with different levels of chemistry training. Finally, I will discuss the potential implications of these findings for chemistry education.
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TELEOLOGICAL EXPLANATIONS
Scientific explanations are commonly based on the identification of causal relations.6 Causal explanations of a phenomenon demand the identification of preceding, or simultaneous, events that determine the occurrence of the phenomenon to be explained. A causal explanation requires the specification of conditions judged to be necessary for something to occur (e.g., a solid expands when heated) and a set of laws or principles that determine the behavior of the system (e.g., heat increases the kinetic energy of particles). However, explanations are sometimes built in terms of the consequences of an event, rather than in terms of its antecedents. This produces teleological explanations.7 For example, if we state “sodium atoms lose one electron to become more stable”, we are building a teleological explanation because we are using the consequences of an event (to become more stable) to explain why the event (loss of an electron) happened. In these types of explanations, entities are portrayed as having purposes or desires, acting to attain certain needs or to fulfill some function.8 The debate around the validity of teleological explanations has a long history. Although many philosophers consider that these types of explanations are legitimate and have strong explanatory power,6,7 scientists tend to reject them and regard them with suspicion. This is particularly true in the area of biology, where terms such as function, role, and purpose are commonly used by many to describe the behavior of living
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organisms9 (e.g., cacti have developed spines to protect themselves from being eaten, eagles wings are designed for soaring). Although biology rests on the belief that all biological phenomena can be ultimately explained in causal terms based on the laws of genetics and evolutionary theory, research studies in biological education10,11 indicate that the use of teleological explanations is pervasive among biology teachers and instructors. While some educators claim that these types of explanations have heuristic pedagogic value,12 others judge that they may foster the development of alternative conceptions.11 Analyses of the use of teleological explanations in physics and chemistry education are sparser. There are indications that anthropomorphism and teleology are present in the instructional explanations of teachers and students in physics13 and chemistry2,3,14 classrooms. My own studies have revealed that teleological explanations are present in common general chemistry textbooks,1 where they are used to provide reasons for the occurrence of chemical transformations. Consider, for example, the following textbook excerpt (ref 15, p 650): If a chemical system is at equilibrium and we add a substance (either a reactant or a product), the reaction will shift so as to reestablish equilibrium by consuming part of the added substance. This statement about Le Châtelier’s principle is teleological because it seems to imply that the change in the system is driven by the system’s goal or intention to reestablish equilibrium. In general, such teleological explanations tend to be linked to the existence of a principle or law (e.g., the second law of thermodynamics) that explicitly or implicitly implies the minimization or maximization of some intrinsic property (e.g., minimization of energy, maximization of entropy).1 This law or principle tends to provide a sense of preferred direction in the evolution of a transformation. In these contexts, explanations built in terms of purposes or desires reduce complex emergent processes into simpler directed events.16 Teleological explanations may be appealing not only because they are simpler than their causal counterparts, but also because of actual human nature. Research in developmental psychology suggests that children are “promiscuously teleological”, that is, they possess a general teleological bias and intuitively reason about entities and events in terms of purpose.17 Children often attribute functions and desires to animate and inanimate entities, and assign a causal role to the perceived goals of objects and events. This teleological bias seems to persist into adulthood. Studies involving college students indicate that they also tend to endorse teleological descriptions of natural phenomena, particularly when the amount of time they have to make judgments and decisions is limited.18 These results suggest that the acquisition of scientific understandings may suppress but not replace intuitive teleological ideas. Work in cognitive psychology indicates that people’s explanations of the behavior of an agent engaged in action are often guided by an implicit bias to interpret such actions as intentional (intentionality bias).19 This often happens when mechanical causes are not explicit, the intention invoked in the explanation is seen as “motivation” for the behavior, and the intention conforms to general and predictable patterns.20 There is evidence to suggest that people may be inherently disposed to invoke intentional explanations in situations of uncertainty, time constraints, or in the absence of relevant knowledge.21 These are the same conditions that students often encounter in chemistry classrooms.
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EXPLORING EXPLANATORY PREFERENCES
Judging the Veracity of Teleological Statements
Psychological studies on people’s teleological bias often involve asking participants to judge the veracity (true or false) or correctness (correct or incorrect) of a variety of sentences describing simple explanations of why things happen.18,19 The set of sentences may include causal and teleological explanations of diverse natural phenomena. On the basis of these types of studies, I decided to explore the extent to which college chemistry students would consider teleological statements about the behavior of atoms, molecules, and chemical systems in general, to be true or false. For this purpose, I wrote several sentences of this kind, which I shared with some of my colleagues teaching the general chemistry courses for science and engineering majors at my institution. I asked them to evaluate whether the statements represented prototypical explanations that they might hear students or instructors use in a chemistry classroom. On the basis of their input, I revised the sentences and asked a group of students finishing the first semester of the general chemistry course to judge the veracity of the teleological statements as part of an online course assignment. The different teleological statements and the percentage of students who considered them to be true are shown in Table 1. As can be seen, this first exploratory study Table 1. Percentage of Students Judging Different Teleological Explanations To Be True Teleological Explanations Sodium atoms tend to lose one electron so that they can have a full electron shell. Oxygen atoms are very reactive because they want to gain two electrons in order to satisfy the octet rule. Atoms combine to form molecules so that they can get the number of electrons that they need to become more stable. Chemical substances tend to react with each other in order to become more stable. When more reactants are added to a chemical reaction in equilibrium, the reaction generates more products in order to restore equilibrium. When the concentration of a solute is not the same in two different parts of a solution, solute particles move from high to low concentrations in order to balance things out.
Response of “True”, % (N)a 83.3 (224) 73.8 (240) 94.4 (216) 83.7 (203) 70.9 (237) 83.0 (236)
a
The N values indicate the total number of students who submitted an answer to a given question.
indicated that over two-thirds of the participants judged these different sentences to be satisfactory explanations of the phenomena described. Notice that I am not claiming that these students actually believed that atoms, molecules, or chemical substances had actual wants or needs. These results only suggest that many of them found such explanations satisfactory and did not seem to question their validity. Choosing between Causal and Teleological Explanations
Intrigued by these results, I wondered to what extent students would prefer teleological explanations over causal explanations of the same phenomena. To investigate this preference, I created four questions that included two alternative explanations, one causal and one teleological, of the same phenomenon. Two of the questions referred to the reactivity of single atoms (oxygen and sodium), while the other two questions focused on the reactivity of classes of substances B
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(acids and bases, oxidizing and reducing agents). As I did with the first study, I asked chemistry instructors in my department to evaluate the validity of the different statements. In particular, I asked them to evaluate whether the causal statements represented satisfactory explanations based on accepted chemical models. I used the revised questionnaire to collect online responses from a group of students (N = 265) finishing the second semester of the general chemistry sequence; these students were asked to select the option that they thought represented “the best (correct) explanation given the choices provided”. The corresponding results are shown in Table 2,
agent acting on a more passive entity. Research in science education suggests that these types of “centralized causal” explanations are also appealing to novice science learners.22−24 This questionnaire was designed to explore the extent to which the presence of different teleological and causal explanations would affect students’ explanatory preferences. The four multiple-choice questions are presented in Box 1.
Table 2. Percentage of Second-Semester General Chemistry Students Selecting Teleological over Causal Statements
1. Oxygen atoms commonly form two chemical bonds when forming molecules with other atoms. What is the cause of this behavior? T1 Oxygen atoms need to gain two electrons to satisfy the octet rule. T2 Oxygen atoms form two bonds with other atoms looking to fill their valence shell. T3 Oxygen atoms form two bonds with other atoms because they want to become more stable. C Oxygen atoms have two semifilled valence orbitals that can be occupied by valence electrons of other atoms. 2. During the reaction between an acid and a base, it is said that the acid donates hydrogen ions (protons) while the base accepts them. Why does the transfer of hydrogen ions happen? T Hydrogen ions are transferred from molecules of the acid to molecules of the base because the molecules want to become more stable. CC1 Molecules of the base attack molecules of the acid and take the hydrogen ions away. CC2 Molecules of the acid attack molecules of the base and give the hydrogen ions away. C Hydrogen ions randomly move between molecules of the acid and the base but it takes less energy for the ions to transfer from the acid to the base than from the base to the acid. 3. Sodium atoms commonly react and form sodium ions with a +1 charge. What is the cause of this behavior? T1 Sodium atoms lose one electron looking to satisfy the octet rule. T2 Sodium atoms lose one electron so that they can have a filled valence shell. T3 Sodium atoms lose one electron because they want to become more stable. C Sodium atoms have one electron in a valence orbital with a higher energy than available valence orbitals in other atoms. 4. During a redox reaction between substances A and B, the oxidizer A gains some electrons while the reducer B loses them. Why does this transfer of electrons happen? T Electrons are transferred from molecules of type B to molecules of type A because the atoms in both types of molecules want to become more stable. CC1 Molecules of the oxidizer attack molecules of the reducer and remove the electrons. CC2 Molecules of the reducer attack molecules of the oxidizer and give the electrons away. C Electrons randomly move between molecules A and B but it takes less energy for them to transfer from B to A than from A to B.
Questions and Response Statements with Paired Teleological and Casual Explanationsa Oxygen atoms commonly form two chemical bonds when forming molecules with other atoms. What is the cause of this behavior? T Oxygen atoms need to gain two electrons to satisfy the octet rule. C Oxygen atoms have two semifilled valence orbitals that can be occupied by valence electrons of other atoms. Sodium atoms commonly react and form sodium ions with a +1 charge. What is the cause of this behavior? T Sodium atoms lose one electron so that they can have a filled valence shell. C Sodium atoms have one electron in a valence orbital with a higher energy than available valence orbitals in other atoms. During the reaction between an acid and a base, it is said that the acid donates hydrogen ions (protons) while the base accepts them. Why does the transfer of hydrogen ions happen? T Hydrogen ions are transferred from molecules of the acid to molecules of the base because the molecules want to become more stable. C Hydrogen ions randomly move between molecules of the acid and the base but it takes less energy for the ions to transfer from the acid to the base than from the base to the acid. During a redox reaction between substances A and B, the oxidizer A gains some electrons while the reducer B loses them. Why does this transfer of electrons happen? T Electrons are transferred from molecules of type B to molecules of type A because the atoms in both types of molecules want to become more stable. C Electrons randomly move between molecules A and B but it takes less energy for them to transfer from B to A than from A to B.
Box 1. Multiple-Choice Questions That Include a Variety of Teleological (T) and Centralized Causal (CC) Response Options, Together with One Causal (C) Explanation
Response of “T”, %b
74.3
74.0
63.8
73.6
a
T indicates a teleological explanation statement; C indicates a causal explanation statement. bN = 265.
which includes the four questions, the associated paired explanations, and the percentage of students who selected the teleological option (T) in their responses. The numbers in Table 2 indicate that a majority of the targeted students selected the teleological explanation over the causal one (C) in each of the questions, revealing the strong appeal of explanations that invoke the tendency of chemical particles and substances to react in order to attain desired states. Exploring the Effect of Training in Chemistry
On the basis of these results, I built a questionnaire that included the four questions in Table 2 written in a multiplechoice format with four, rather than two, response options. Questions 1 and 2, which referred to the reactivity of single atoms, included the two explanations listed in Table 2 plus two additional teleological choices. Questions 3 and 4, focused on the reactivity of classes of substances, included the two explanations shown in Table 2 plus two other causal explanations that attributed the described phenomena to the action of an active C
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Figure 1. Percentage of students in each targeted group: General Chemistry I (GCI), General Chemistry II (GCII), Organic Chemistry II (OCII), and Incoming Graduate Students (IGS), who answered the four questions shown in Box 1, selecting from the different response options: Teleological (T), Causal (C), and Centralized Causal (CC).
need to satisfy the octet rule (Q1, T1). This was not, however, the preferred choice in Question 2, where the reactivity of sodium atoms was often seen as driven by these atoms’ tendency to fill their valence electron shell (Q2, T2) or to become more stable (Q2, T3). Responses by OCII students and IGS students to Question 3 revealed the likely influence of common ways of talking and representing reaction mechanisms in organic chemistry courses, in which bases are commonly depicted as “attacking” acids (Q3, CC1). This was the only question in which the dominant choice made by a group of students (OCII) was not the teleological option. The low selection frequency of equivalent centralized causal explanations in Question 4 suggests that the response pattern observed in Question 3 may be specific to acid−base reactions (and, potentially, nucleophile−electrophile interactions). For redox processes, the teleological option (Q4, T) describing electron exchange as driven by reactants’ stability needs was the most common choice in all groups.
To explore the explanatory preferences of students with different levels of training in chemistry, I asked four different groups of students to complete an online version of the questionnaire. These groups included students who were: In their first week of the first semester of the general chemistry course (GCI, N1 = 512) Finishing the second semester of the one-year general chemistry sequence (GCII, N2 = 490) Finishing the second semester of the one-year organic chemistry sequence (OCII, N3 = 192) Incoming graduate chemistry students at my institution (IGS, N4 = 38) The results of this third study are summarized in Figure 1, which shows the frequency of selection of different response options for Questions 1−4. As can be seen in Figure 1, an average of only 20% of the students in the different targeted groups selected the causal statement (C) as a satisfactory explanation in each of the four questions. Analysis of standardized residuals for different groups’ choices showed no major influence on the results of χ2 test statistics for students’ selection of the causal explanation, except in Question 1 for which a significantly larger fraction of the incoming graduate students (IGS, 37%) chose the causal option. Overall, preference for the teleological explanations was dominant regardless of level of training in chemistry. Nevertheless, differences in the choices made by different groups are worth highlighting. For all student groups, the most appealing explanation for oxygen’s bonding capacity in Question 1 referred to the atoms’
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DISCUSSION AND IMPLICATIONS The results of these exploratory studies revealed that college chemistry students had a significant preference for teleological explanations of chemical reactivity, regardless of their level of training in the discipline. This preference may or may not have stemmed from the belief that atoms, molecules, or chemical substances have actual needs or wants, but in any case revealed the strong appeal of explanations that invoke the attainment of a more desirable (stable) state as a major driving force for chemical processes. Course work in chemistry seemed to have a D
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teleological bias (i.e., teachers and students tend to explain chemical reactivity in terms of atoms wants or needs for an octet of electrons) has on conventional chemistry education. Finally, I suspect that teleological explanations are appealing to chemistry students because they are actually productive in making predictions about the outcome of chemical interactions and processes. The assumption that interacting atoms will gain, lose, or share a specific number of electrons to satisfy the octet rule or attain stability often allows us to make predictions about bonding capacity and types of ions formed. Thinking that a mixture in chemical equilibrium will react in order to counteract the effects of a change is productive in making predictions about relative shifts in the concentrations of reactants and products.1
significant influence on students’ explanatory preferences for specific types of chemical reactions, as indicated by the overselection by the more advanced students of a centralized causal mechanism to explain acid−base reactivity. Nevertheless, this shift in preference was highly specific and did not transfer to other types of chemical reactions. What May Be behind Students’ Choices?
More in-depth, qualitative research studies would be needed to explore the major reasons that drove so many different students to select teleological explanations over causal ones. Although it might be possible that the wording of the questions themselves somehow biased students’ answers toward the teleological choices, the consistency of results across different questions suggests that the preference has deeper roots. Given that the central goal of this paper is to stimulate reflection on this issue, it is worth speculating on potential reasons for students’ preferences based on existing educational and psychological research in the areas of human reasoning and explanation. One possible reason behind the observed choices is that teleological explanations are seen as simpler than causal explanations, which makes them more appealing. Research in cognitive psychology suggests that when people are confronted with different explanations of the same phenomenon, they tend to judge the simpler explanations as better and more likely to be true.25 Simpler explanations in these studies tend to invoke fewer causes, involve simpler mechanisms, or both. This preference for simplicity often implies that a large amount of evidence may need to be provided before a complex explanation will be favored over a simpler alternative. Another potential reason for students’ preferences has to do with the comprehensibility of the different explanations. Research in this area indicates that people tend to agree more strongly and are more intensely persuaded by comprehensible than incomprehensible arguments.26 Science students are known to have difficulties understanding the type of probabilistic arguments used to explain emergent processes, such as diffusion, natural selection, and chemical equilibrium.23,27,28 From this perspective, one could suspect that many participants found the types of causal explanations included in Questions 3 and 4 in Box 1 less comprehensible than the teleological or centralized causal options. This lack of comprehension may have driven students away from the causal alternatives. Students’ choices may have also been influenced by wellknown reasoning heuristics applied by people when making decisions under conditions of uncertainty, limited time, or low motivation.29 In particular, we have shown that chemistry students often rely on a “recognition” (or familiarity) heuristic to rank chemical substances or processes based on a given property (e.g., solubility, acid strength).30 The recognition heuristic is based on the following general rule: “If one of several objects is recognized and the others are not, then infer that the recognized object has the higher value with respect to the selection criterion.” Participants in our studies had likely more exposure to teleological explanations of chemical phenomena than to other types of explanations, which may have provided a sense of familiarity that influenced their answers. Indeed, one may argue that many chemistry students are mostly exposed to teleological explanations of the chemical phenomena represented in the questionnaires,2,3 and thus participants in our study may have not actually known any alternative explanations. Taber3,31 has extensively discussed the strong influence that an “octet framework” with an underlying
What To Do?
Simplicity, comprehensibility, familiarity, and productivity may be among the major factors behind the response patterns found in our exploratory studies. It could also be that, as mentioned previously, humans are inclined from a very early age to assume intentionality in the behavior of entities in our world.17−19 Recent studies involving physical scientists indicate that even science experts exhibit teleological biases, despite their specialized training and advanced knowledge.32 Whatever the causes may be for the strong appeal of teleological explanations, we ought to carefully reflect on the implications of the outlined results for chemistry education. The major concern that I have with the overuse and overselection of teleological explanations to make sense of chemical reactivity, either at the atomic or the substance levels, is that these types of explanations likely create a false sense of understanding that is known to stop people’s search for better accounts of a phenomenon.33 People frequently believe that they know or understand more than they actually do about the structure and mechanism of systems and devices.34 This illusion of explanatory depth occurs because we are likely to confuse a superficial understanding of the consequences of processes (e.g., have a filled valence shell, gain stability, restore equilibrium) for a deeper understanding of underlying mechanisms. Teleological explanations are problematic in education because they provide a cognitively cheap way of satisfying a need for explanation without having to engage in more complex mechanistic reasoning.35 Given the various and likely deep cognitive roots of students’ preference for teleological explanations, it would be ineffective and impractical to suggest that they must be avoided at all costs in chemistry classrooms. Rather, we should use them as springboards for discussions about the strengths and weaknesses of different types of explanations. We should create opportunities for students to compare and contrast teleological and causal mechanistic explanations of the same system. This implies that we should open spaces in chemistry classrooms at all educational levels to more deeply and systematically engage students in the analysis, development, application, and evaluation of mechanistic causal explanations of chemical phenomena. Many properties of chemical substances and of the processes in which they are involved are the result of the dynamic interactions of myriads of particles. They are, in this sense, emergent phenomena that can be explained using probabilistic causal models.7,23,28 These dynamic models allows us to connect the properties of submicroscopic particles with those of macroscopic systems through the analysis of local interactions and their effects on probabilistic events.36 For example, proton transfer in acid−base reactions can be modeled as a random E
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(15) Brown, T. L.; Le May, H. E.; Bursten, B. E.; Murphy, C. J. Chemistry: The Central Science, 10th ed.; Pearson/Prentice Hall: Upper Saddle River, NJ, 2006. (16) Chi, M. T. H. J. Learn. Sci. 2005, 14 (2), 161−199. (17) Kelemen, D. Trends Cogn. Sci. 1999, 3 (12), 461−468. (18) Kelemen, D.; Rosset, E. Cognition 2009, 111, 138−143. (19) Rosset, E. Cognition 2008, 108, 771−780. (20) Lombrozo, T.; Carey, S. Cognition 2006, 99, 167−204. (21) Kelemen, D.; DiTanni, C. J. Cogn. Dev. 2005, 6 (1), 3−31. (22) Resnick, M. Turtles, Termites, and Traffic Jams: Explorations in Massively Parallel Microworlds; MIT Press: Cambridge, MA, 1994. (23) Perkins, D. N.; Grotzer, T. A. Stud. Sci. Educ. 2005, 41, 117− 165. (24) Talanquer, V. Int. J. Sci. Educ. 2010, 32, 2393−2412. (25) Lombrozo, T. Cognit. Psychol. 2007, 55, 232−257. (26) Scharrer, L.; Bromme, R.; Britt, M. A.; Stadler, M. Learn. Instr. 2012, 22, 231−243. (27) Jacobson, M. J.; Wilensky, U. J. Learn. Sci. 2006, 15, 11−34. (28) Chi, M. T. H.; Roscoe, R. D.; Soltta, J. D.; Roy, M.; Chase, C. C. Cognit. Sci. 2012, 36, 1−61. (29) Shah, A. K.; Oppenheimer, D. M. Psychol. Bull. 2008, 134, 207− 222. (30) Maeyer, J.; Talanquer, V. Sci. Educ. 2010, 94, 963−984. (31) Taber, K. S. Int. J. Sci. Educ. 1998, 20 (5), 597−608. (32) Kelemen, D.; Rottman, J.; Seston, R. J. Exp. Psychol. Gen. 2012; Advance online publication, DOI: 10.1037/a0030399. (33) Trout, J. D. Philos. Sci. 2002, 69, 212−233. (34) Rozenblit, L.; Keil, F. C. Cognit. Sci. 2002, 26, 521−562. (35) Russ, R.; Scherr, R. E.; Hammer, D.; Mikeska, J. Sci. Educ. 2008, 92, 499−525. (36) Levy, S. T.; Wilensky, U. J. Sci. Educ. Tech. 2009, 18, 224−242. (37) Tasker, R.; Dalton, R. Chem. Educ. Res. Pract. 2006, 7 (2), 141− 159. (38) Pollard, J.; Talanquer, V. Chem. Educator 2005, 10, 36−40. (39) Wieman, C. E.; Adams, W. K.; Perkins, K. K. Science 2008, 322, 682−683. (40) PhET Interactive Simulations, University of Colorado at Boulder. Freely available at http://phet.colorado.edu/ (accessed Sep 2013). (41) Xie, Q.; Tinker, R. J. Chem. Educ. 2006, 83, 77−83. (42) Molecular Workbench, Concord Consortium. Freely available at http://mw.concord.org/modeler/ (accessed Sep 2013). (43) Stieff, M.; Wilensky, U. J. Sci. Educ. Tech. 2003, 12 (3), 285− 302. (44) Talanquer, V. J. Chem. Educ. 2006, 83 (5), 811−816. (45) Shtulman, A.; Valcarcel. Cognition 2012, 124, 209−215. (46) Amsel, E.; Klaczynski, P. A.; Johnston, A.; Bench, S.; Close, J.; Sadler, E.; Walker, R. Cognit. Dev. 2008, 23, 452−471.
process in which the probabilities of proton exchange from the acid to the base, and vice versa, differ due to energetic and entropic constraints imposed by composition and structural characteristics of the particles involved. Although chemistry teachers and instructors may consider that their students will be unable to understand such types of models, research in science education indicates that most students are quite capable of developing and applying complex models with proper scaffolding.27 Nowadays, free online access to powerful interactive resources can be used to support this type of thinking by actively engaging students in the use and development of dynamic visualizations37 and simulations38 of diverse chemical systems. That is the case of the interactive simulations built as part of the Physics Education Technology (PhET) project39,40 and the Molecular Workbench initiative.41,42 Additionally, concrete examples of chemistry curriculum projects, such as Connected Chemistry,36,43 have been specifically designed to foster dynamic, multilevel thinking. Engaging students in the analysis and evaluation of different types of explanations, from teleological to probabilistic causal, of chemical phenomena could also help raise students’ metacognitive awareness about the various cognitive biases that are likely to influence their reasoning when analyzing the properties and behaviors of chemical entities and processes.44 According to recent work in cognitive psychology, scientific knowledge helps to mask and control, rather than replace, human intuitions.45 If that is the case, students may be best served by instruction that helps them develop metacognitive skills to control intuitive responses and compare and contrast them with the products of more effortful analytical reasoning.46
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AUTHOR INFORMATION
Corresponding Author
*E-mail:
[email protected]. Notes
The authors declare no competing financial interest.
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REFERENCES
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