8Nakhleh,M.B.. Are Our Students Conceptual Thinkers or Al- gorithmic Problem Solvers? [J]. Journal of Chemical Education, 1993, 70 (1) : 52-53.
9Koch, H.. Simplifying Stoichiometry [J]. The Science Teach- er, 1995, (62) : 36-39.
10John Sweller, Graham A. Cooper. The Use of Worked Ex- amples as a Substitute for Problem Solving in Learning Algebra [J]. Cognition and Instruction, 1985, 2 (1) : 59-89.
