In this paper, the presentation of the sequence of gas laws is examined to identify cognitive gaps which can hinder student understanding of the concepts involved. Analysis of 14 physics textbooks used in Australian secondary schools and questionnaires from 104 science teachers provided the data for the study. Analysis of the teachers' reports reveals features of the gas law sequence which are inconsistent with the textbook analysis; namely, a low usage of the historical sequence for the gas laws, the use of a sequence which is not necessarily logical, and the use of a simple to complex sequence with no cognitive gaps. The manner in which textbooks can constrain teachers' presentation of concepts and exercises is discussed.
de Berg, K.C., & Treagust, D.F. (1992). The presentation sequence of gas properties by physics textbooks and science teachers' reports. Australian Science Teachers Journal, 38(2), 70-75.