CHEMISTRY TEACHERS PEDAGOGICAL CONTENT KNOWLEDGE ON CHEMICAL EQUILIBRIUM

Chemical Equilibrium is a central concept in the learning of chemistry and remains one of the most difficult to teach and to learn. Therefore, this topic is the subject of many studies in science education with different goals: to know the difficulties of student learning, misconceptions, explanations for these errors, and so on. Two years ago we present in EDULEARN10 a teaching-learning sequence built in the framework of School Science, to propose the construction of a Chemical Equilibrium model based on thermodynamic (phenomenological) arguments and in agreement with constructivist theories. In the design of that sequence, we take as a starting point the alternative conceptions, prior knowledge and the various cognitive abilities of the students. Our hypothesis was that in this theoretical framework, the students could construct the concept in a better manner. In the past few years, teacher educators and educational researchers have emphasized the need to developed the pedagogical content knowledge (PCK) of the professors, as a useful tool to enhance learning and although his importance, there are many few articles about the PCK of chemical equilibrium. Because of that, before testing the sequence with students, we decided investigate the PCK of five professors of high school and four undergraduate Mexican teachers. Among other things, we want to know what are de activities that the teachers proposed to overcome the difficulties in teaching this concept. In two of the group of the teachers selected, we will probe the sequence designed. To document the PCK, we decided to use the methodology proposed by Loughran and coworkers.