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Asia-Pacific
Forum on Science Learning and Teaching, Volume 6, Issue 2, Article
6 (Dec., 2005) Muammer CALIK and Alipasa AYAS An analogy activity for incorporating students' conceptions of types of solutions
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Asia-Pacific
Forum on Science Learning and Teaching, Volume 6, Issue 2, Article
6 (Dec., 2005) Muammer CALIK and Alipasa AYAS An analogy activity for incorporating students' conceptions of types of solutions
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Introduction
There are three dynamic domains in the cognitive system; conception, categories, and frameworks (Gilbert & Watts, 1983), which have a rigid relationship with each other. Firstly, conceptions are developed by means of individual view or hypothesis. Then, based on conceptions categories emerge. Finally, frameworks are generated by taking into consideration categories. This means that the better conceptions are constructed or comprehended, the better the other steps are improved. Since the first step depends on the students' experiences or hypothesis, it is possible that miscellaneous conceptions different from the one accepted by scientific community may arise. These conceptions generally named "misconception", "alternative conception", "children's science" (e.g., Helm, 1980; Hewson & Hewson, 1984; Nakhleh, 1992; Costu, Unal & Ayas, 2004) are also pieces of intellectual thought (Schmidt, 1997). Further, Stavy (1991) pointed out that there is a dynamic competition in the cognitive system in which the strongest concept dominates. This means that if an alternative conception outweighs a scientific one in this dynamic process, it affects the subsequent understanding or structure. At that point, what will we do as science educators? Do we ignore the alternative conceptions or endeavor to overcome them?. Of course, we should struggle to remedy them if we desire to get students to have scientific comprehension at a more sophisticated level.
Since alternative conceptions are important for further learning, one is able to find numerous studies if one enters "misconception" or "alternative conception" as key words in data bases. But, elicitation of alternative conceptions does not mean dealing with all of them. However, diagnosing them is central for remediation. Hence, much research has been conducted into underlying topics such as "particulate nature of matter", "dissolving and solutions", "combustion", "chemical bonding"(Griffiths, 1994). Amongst these underlying topics, solution chemistry, which is a pre-requisite for some topics such as electrochemistry, acids and bases, chemical equilibrium, is one of the most investigated topics because of its importance. Studies on solution chemistry have concentrated on various perspectives as follows: dissolution, the nature of solutions, solubility, energy in solution processes, effects of temperature and stirring to dissolution of solid in liquid, conservation of mass during dissolution process, types of solutions--unsaturated, saturated and supersaturated and vapor pressure lowering, solubility of a gas in water and the relationship between vapor pressure and boiling point, and strategies to overcome students'conceptions (Calik, Ayas & Ebenezer, 2005).
Within the aforementioned perspectives, only two studies, Pinarbasi and Canpolat (2003) and Calik and Ayas (2005a) focused on eliciting students' conception on types of solutions. The former stated that many students thought a solution in equilibrium involved an undissolved solute was a supersaturated solution. In other words, most of students under investigation had difficulty in differentiating the distinction between a supersaturated solution and a saturated solution, so that the students may see a saturated solution as supersaturated if dissolved and undissolved solute are in equilibrium. Finally, they asserted that seeing undissolved solute as a component of solution forms the idea that a supersaturated solution includes the undissolved solute. The latter attempted to draw out students' comprehension related to dilute and concentrate solutions. They pointed out that some of the students at lower grades tended to exploit some hypothesis such as if solution in Beaker B is a saturated solution, solution in Beaker A must be an unsaturated solution. Moreover, they emphasized that some of the grade 7, grade 8 and grade 10 students stated that both of the solutions are the same because, both of them include sugar. However, no teaching strategy has been offered with regard to types of solutions to challenge students' alternative conceptions or replace them with scientific one. However, some alternative strategies in other different perspectives of solution chemistry such as a hypermedia environment to animate the dissolution process (Ebenezer, 2001), a unit on solution chemistry working collaboratively with a chemistry teacher (Ebenezer & Gaskell, 1995), a group exploration to inquire about the solubility of salt, sugar, potato flour, baking soda (Kaartinen & Kumpulainen, 2002), a teaching-learning sequence on the particle model of solubility (Kabapinar, Leach & Scott, 2004), a worksheet to incorporate students' conceptions of conservation of mass in the dissolution process (Johnson & Scott, 1991), and an analogy about conservation of matter during dissolution process (Taylor & Coll, 1997) were devised and implemented.
Since students' pre-existing ideas influence their learning, teachers need to explore them during lesson sequences. However, teachers do not know how to exploit students' conceptions in the teaching-learning process (e.g., 1994; Matthews, 2002). On the other hand, given that the science curriculum is replete with many topics, they may not have enough time to design new activities even if they know how to design them. We, as science educators, ought to assist teachers with activities in addressing and incorporating students' conceptions into lesson sequences. Hence, the present article intends to unlikely design an activity on the types of solutions -- unsaturated, saturated, supersaturated, dilute and concentrate -- based on the assumption that learners actively construct and transform their own meanings, rather than passively acquire and accumulate knowledge transmitted to them (e.g., Ayas, 1994; Rezai & Katz, 2002; Taber, 2000; Vosniadou & Brewer, 1987).
Copyright (C) 2005 HKIEd APFSLT. Volume 6, Issue 2, Article 6 (Dec., 2005). All Rights Reserved.
