In this work, the beliefs of undergraduate students from Brazil and Portugal on the use of visual tools in teaching chemistry, which have increasingly been introduced in the areas of teaching/learning in these two countries in recent years, have been investigated. An interpretative analysis of the results shows little familiarity of students with specific points of the theme, beyond a poor conception about the way the visualization tools influence the construction of scientific concepts.

Visualization is a fast-growing field in science education. This review covers 171 articles published between 2001 and 2010 in 14 science education journals. Major findings include: i - despite the predominance of English speaking countries, interest in the topic has increased in several countries; ii - qualitative research is increasing, but quantitative methodologies prevail; iii - the role of peer interaction in group activities is little investigated; iv - research on the way students and teachers use visualization tools is increasing, but most publications focus on the tools; v - structure of matter remains the most common subject covered.

Molecular modeling enables the students to visualize the abstract relationships underlying theoretical concepts that explain experimental data on the molecular and atomic levels. With this aim we used the free software "Arguslab 4.0.1" (semi-empirical method) to study the reaction of 1-chloropropane with ethoxide in solution, known to lead to methyl propyl ether, through the S N2 mechanism, and propene, through the E2 mechanism. This tool allows users to calculate some properties (i. e. heat formation or electric charges) and to produce 3D images (molecular geometry, electrostatic potential surface, etc.) that render the comprehension of the factors underlying the reaction's progress, which are related to the structure of the reagents, and the process kinetic clearer and easier to understand by the students