In the information age, the significance of visual representations cannot be underestimated or considered trivial. Graphical literacy, encompassing knowledge and skills in interpreting visual representations of scientific objects and phenomena (referred to as inscriptions), plays a crucial role in this context. However, many students struggle with using and comprehending inscriptions, and they are seldom encouraged to engage in argumentative practices within science classes. The literature emphasizes the importance of incorporating authentic scientific practices into science education, which involve using inscriptions for rhetorical purposes. This promotes the association between graphical literacy and scientific argumentation, enhancing the critical use of inscriptions. This study aims to implement and analyze teaching activities that simultaneously foster graphical literacy and scientific argumentation through the resolution of interrupted case studies. Three case studies were created focusing on heavy metal contamination of water resources and its effects on human health, based on peer-reviewed articles. Due to the Covid-19 pandemic, the cases were implemented remotely in a scientific communication course offered to undergraduate chemistry students. The students worked in groups, delivering oral presentations to discuss the resolution of the cases. The quality of the oral arguments developed during these presentations was analyzed based on their epistemic status and lexical cohesion, employing theoretical and methodological frameworks proposed by Gregory Kelly and collaborators. Additionally, the IRaMuTeQ was utilized to facilitate the processing of these analyses. The analyzed oral arguments integrated conceptual understanding of the problem with empirical evidence obtained during the resolution of the case studies. The conclusions drawn were supported by information of various natures. The arguments also exhibited lexical cohesion, with propositions from different epistemic levels connected through the sharing of morphemes, forming a network of evidence to support the conclusions. The analysis of graphical literacy was conducted through interactional analysis, resulting in the formulation of ten claims pertaining to the skills of selecting, producing, and communicating with inscriptions. These claims were discussed in relation to studies conducted by Wolff-Michael Roth, Lilian Pozzer, and collaborators. The claims demonstrated the utilization of these skills in various situations during the oral presentations, including attributing a theme to the presentation, presenting the case studies' narratives, explaining concepts, presenting and comparing experimental procedures and sampling points, and discussing data for the case studies resolution. The results of this study provide valuable insights into critical aspects influencing the use of inscriptions for rhetorical purposes in multimodal scientific communication scenarios. Additionally, instructional recommendations are proposed for teaching chemistry and dev...