In this study, students' understanding of both, the particulate nature of matter and the change of states were investigated in relation to three cognitive variables: logical thinking (developmental level), field-dependence/field-independence and convergent/divergent thinking. The study took place in Greece with the participation of 329 ninth-grade junior high school pupils (age 14-15). A stepwise multiple regression analysis revealed that all of the above mentioned cognitive variables were statistically significant predictors of the students' test scores concerning their understanding the particulate nature of matter and physical changes such as melt, evaporation, boiling and condensation. Among the three predictors, logical thinking seems to be the most dominant one. Moreover, a theoretical analysis is provided that relates logical thinking and cognitive styles to the nature of mental tasks involved when learning this specific domain material.