Collective authorship or a text written by more than one person in a computer-based environment can bring significant benefits to chemistry teaching, mainly concerning flexibilizing forms of interaction among those involved and collaborative construction of knowledge. This work investigates collective authorship activities based on constructing argumentative texts in groups with the participation of undergraduate chemistry students. In the activity, those involved, divided into groups, followed the textual production process aiming to present a joint solution for case studies. It was possible to understand aspects of collective work in the authorship process in question regarding collaboration and cooperation based on two perspectives considered crucial for collaborative writing: conditions offered by the electronic platform called eduqui.info, and in which contexts these possibilities were present in the writing process; and the organisational aspects of the activity. Overall, groups chose to collaborate more than cooperate. In other words, data shows that most of the students worked collaboratively in groups.