Rankin's comments on our article, "Chemistry Students' Conceptions of Solubility: A Phenomenography," are organized around three very different concerns which he has described in somewhat succinct and, we might add, provocative subheadings of: "Nothing New," Two Different Perspectives of Conceptions," and finally "A Question of Trustworthiness." We will respond to each of these issues in turn.
Let us begin with Rankin's claim that the work reported in the aforementioned article is "substantially the same work that was reported in an earlier study by Ebenezer and Gaskell (1995)." It should be very clear to a discerning reader that these two studies are indeed related as both articles clearly indicate that the work was a product of Ebenezer's doctoral dissertation and readers are referred to it in both articles for more detailed documentation and argumentation than is permitted in journal activities. For Rankin to draw a conclusion that they are "substantially the same" we suggest comes from a significant misunderstanding of the primary objectives of the two articles. The focus of the Ebenezer and Gaskell (1995) article was on clarifying the nature of the changes in students' understanding about a set of scientific concepts related to chemical solubility as a result of an instructional intervention whereby Ebenezer worked collaboratively with a classroom teacher in an effort to design a richer learning environment. A further contribution of this article was to critique aspects of some of the existing models of conceptual change by drawing upon a perspective of cognition, developed by Marton (1981Marton ( , 1989) ) and colleagues, called "phenomenography."
In contrast, the primary objectives in our article were threefold: first, to carefully document the procedures that were used to generate the categories of students' conceptions; second, to provide a much more in-depth discussion and rationale for adopting a phenomenographic perspective in this type of research; and, finally, to discuss some of the pedagogical implications of this work in the context of a rapidly growing literature in this field. In the initial drafting of these two studies it was intended that the Ebenezer and Erickson (1996) article precede the Ebenezer and Gaskell (1995) article, because it provided the substantive and methodological claims for the students' conceptions of solubility that were to be used in the 1995 article to discuss changes brought about by instruction. While this intended order of publication did not happen, we nonetheless submit that this does not diminish the value and importance of our 1996 article. Because we are arguing for a significantly different way of thinking about