Evidence from the research literature suggests that a variety of cognitive factors are responsible for chemistry achievement. This investigation examined the role that four cognitive factors, namely, prior knowledge, formal reasoning ability, memory capacity and field independence/dependence, play on achievement in chemistry as measured by tests of laboratory application, chemical calculations, and content knowledge. The sample was comprised of grade 11 students from 11 high schools who were following the same chemistry syllabus. Correlational analysis, multiple regression analysis and path analysis were performed on the data and all produced similar results. Prior knowledge and formal reasoning ability were each statistically significantly related to variation in chemistry achievement. Field dependence/independence and memory capacity played no significant role in chemistry achievement. The educational implications of these results were discussed. (Author/TW)