The research reported in this study was designed to answer three questions: (a) What misconceptions do eighth grade students have concerning the chemistry concepts from their textbooks. (b) How is reasoning ability related to misconceptions concerning chemistry concepts. (c) How effective are textbooks in teaching an understanding of chemistry concepts? Five chemistry concepts were used in the study: chemical change, dissolution, conservation of atoms, periodicity, and phase change. Problems concerning the five concepts were given to 247 eighth-grade students in order to assess the students' degree of understanding of chemistry concepts and to identify specific misconceptions. Two pencil-and-paper Piaget-type tasks were used to assess intellectual level. A comparison of intellectual level and scores on the chemistry concepts showed moderate correlations. However, the small number of formal operational students in the sample makes these results inconclusive. A study of the level of understanding of the five chemistry concepts and the nature of the misconceptions held by students indicate a general failure of textbooks to teach a reasonable understanding of chemistry concepts.