The teaching of mater cohesion (covalent bond, ionic and molecular interactions) makes one's first appearance, in France, in grade 10 and continues in grade 11. Number of centuries have been necessary for working out the different concepts involved. It has been required for this to quit the perceptible material world and to elaborate representations placed on the other side of this world. The objective of this historic approach is to make in evidence that a new idea put a long time before to implant in the mind and become operational. She comes up again a lack of understanding, very decided views, etc. If a strong link can not be established between a historic elaboration of these abstract concepts and their constructions by students (contexts are different), we can imagine that students could encounter difficulties and take time to assimilate them.