The concept of chemical bond is considered crucial by many researchers in the field of Science Education as it is the basis for the understanding and assimilation of many others within the fields of chemistry, biology and geology.

On the other hand, referring to the psychopedagogical aspects of the issue, it can be said that, in recent years, as much the pedagogical literature in general, as in the field of sciences in particular, several psychological models that serve as a basis for the curriculum design have been pointed out. One of these is the model proposed by Ausubel, considering that the students as well as being active in their methods of work, should undertake not arbitrary activities and meaningless activities. JD Novak and Gowin are two of the researchers who have done more work on the fulfilment of Ausubel instructional principles.

They have used the technique of concept maps as a tool to express and coordinate concepts or behaviours through graphic representation. The present work shows the way in which this technique has been introduced in the teaching of chemistry for pre service teachers of primary education.

In this paper we present the use of the Cmpatools software (free software developed by the Institute for human and machine cognition) in order to help to construct concept maps in any field of knowledge). The topic chosen for it has been “Chemical bonding and properties of substances” because this topic is considered as basic in the field of Science Education for the understanding and assimilation of many other concepts as much in chemistry as in biology or earth science. Concept maps have proved to be a useful and convenient instrument for highlighting the students' concepts, their previous knowledge, and, sometimes, their habits, worries, expectations as well as their way of thinking. In our case this technique has allowed the students to acquire a series of knowledge and skills important for a professional of the pedagogical ambit such as the future primary education teachers they pretend to be.

The application of this technique along the teaching of the subject enabled the students to acquire greater skills during the study when reading the contents of the texts and bibliographies related to each subject and extract the concepts that are essential in connection with the proposed task. In the same way, they have been able to make generalizations of the contents under consideration, to correct misconceptions or relationships established incorrectly, as well as develop content schemes that can be used in presentations at seminars of the subject and in the oral examination or in written summaries.