Das werden-Passiv in Schulbüchern der Chemie

Abstract The competent use of the specific language of school subjects is fundamental for successful learning and teaching in school. For a language-sensitive design of lessons and empirical foundation of didactic and methodical concepts, knowledge of how students read a text is needed as well as evidence-based knowledge of formal and functional aspects of subject-specific language. A corpus analysis confirms that the passive is a prototypical construction in chemistry textbooks. Thus the competent handling of those sentences is a relevant aspect of subject-specific language competence. The verbs used in the passive sentences in books included in the corpus are predominantly morphologically complex, and can be indicated as chemistry-specific lexis, e. g. related to the sub-microscopic level. Furthermore, they are commonly used in conjunction with abstract agents. On the other hand, these verbs are also encountered to students in everyday (i. e. non-subject-specific) contexts but in these contexts they diverge semantically and are commonly used in conjunction with a human agent. Therefore, the function of the passive sentences differs: While passive sentences with a human agent allow an expression of anonymised actions, the passive sentences with abstract agents enable the verbalisation of abstract processes. The distribution of those functional distinction differs between school subjects and contexts. Abstract agents in passive sentences can support the maintenance of pre-instructional concepts of students, especially if the verbs are not obviously specific for the context of chemistry. Therefore, a specific language-education for school subjects is needed which includes the analysis of formal and functional aspects. The results of the corpus analysis can be used for context-based scaffolding in language-sensitive chemistry lessons.