This was a quantified study on the learning of certain theoretical topics in general chemistry as influenced by two methods of visual technique (single concept films, overhead projections). Four classes of chemistry students (non-science majors) registered in sections on a random basis, participated. Objective, multiple choice tests on each of the selected topics were constructed, tested for reliability and validated. Two chemistry sections of the same course were tested the first year of the experiment (repeated again the second year); one section was designated as the experimental group and the other the control for the first topic. Groups were alternated for all six topics to cancel out individual differences. In the lecture-discussion sessions, only the experimental group had access to visual aids integrated with class presentation. Test scores were compared by analysis of variance and F tests. The p values converted from the F ratios were transformed to chi-square statistics. Results were tested for significance at the 5% level. Results differed with the type of topic approached but it was observed, subjectively, that student interaction with the use of silent film-loop, stopped at any point, or with the projectual, showed a greater degree of involvement with the topic. (Author/EB)