Chemists have bemoaned for years their students' inability to solve problems in introductory chemistry courses. However, at least part of this inability must be attributed to the fact that chemists have historically tried to teach their students to solve problems by doing nothing more than working examples. In recent years, chemists have begun to realize the importance of general strategies or heuristics in problem-solving, and they have become particularly enthralled with the "road map" approach to problem-solving. There is abundant evidence, however, that students who understand this approach all too often still cannot solve "simple" stoichiometry problems. The hypothesis behind the research discussed in this paper is the assumption that there is a preliminary stage in problem-solving which most chemists have neglected. During this preliminary stage, relevant information is disembedded and the problem is restructured. Until this stage is successfully completed, students cannot proceed on to the analytic stage in which the road map heuristic can be applied. Preliminary evidence supporting this hypothesis is presented which suggests that there is a linear correlation between students' ability to handle disembedding and cognitive restructuring tasks in the spatial domain and their ability to solve "simple" stoichiometry problems. Nine references are listed. (Author/JN)