This study analysed the distribution of questions from the gas law chapters of four high school and four college chemistry textbooks based on six variables--Book Type (secondary "versus" introductory college), Cognitive Skill (lower-order "versus" higher-order), Question Format (calculation "versus" multiple-choice "versus" short-answer), Question Placement (in-chapter "versus" end-of-chapter "versus" test-bank), Question Type (qualitative "versus" quantitative), and Representation (macroscopic "versus" particulate "versus" symbolic). The questions in these chapters were homogeneously distributed for the Cognitive Skill and the Representation variables, but showed differences in question distribution based on the Book Type, Question Format, Question Placement, and Question Type variables. The loglinear analysis method used in this study provides one way to analyse the distribution of different types of questions appearing in chemistry textbooks, and these differences in question distribution can be helpful for textbook authors to evaluate the types of questions appearing in their textbooks and how they are presented, and can be helpful for chemistry instructors to determine how they need to adapt their instructional lessons to prepare students for course examinations or college/career placement examinations. Contains notes and references.