This article reports the findings of Phase II of our study of student use of web-based tutorial materials for general chemistry and student understanding of chemistry concepts. We have found that students who use the web site valued the aspects of visualization of chemistry concepts and availability of materials online. In our analysis of student understanding of chemistry concepts by way of concept maps, we found that students who used the web site showed a similar level of understanding of chemistry to that of the students who did not use the web site, but that the web site users attempted to make more concept map links about the relevant chemistry concepts. Similarly to our finding in Phase I of the study, most students thought that the Web was a good way to get help learning chemistry. (Contains 2 figures and 3 tables.)