This research be interested in written language and sign systems in learning scientific concepts. It will show that the effectiveness of teaching about the gas on students varies with semiotic registers, as text or diagram. Our theoretical framework is in physics education and adopts a socio-constructivist approach using work on the semiotic. Based on a pre and post test (using text and diagram) given to 90 students at the upper-secondary school level (Grade 10 [15-year-old students]), we analyzed their responses with the Sphynx software. Our analysis is reproducible and all our results are statistically significant at the Chi2 test. Its show that after teaching students progress more and are much more efficient: (a) in the diagram to use ideas on particle aspect and the uniform distribution of gas and (b) in the written text to mobilize ideas on the action of the gas. Furthermore, it seems that there is a probable influence between semiotic registers used during teaching on a specific concept about gas and the importance of the evolution of students' ideas on this concept in the same semiotic register.
