This study explores the pedagogical challenges in teaching chemical equations, focusing on the ability to balance chemical equations and understanding related basic chemical concepts among chemistry teacher students. Based on Johnstone’s representation theory, we examined the efficacy of digital tools designed to enhance equation-balancing skills. The key findings of this study seem to be the disconnection between students’ procedural proficiency in balancing equations and their conceptual understanding of underlying chemical reactions. Surprising was the relatively low ability to balance chemical equations when compared to the expected level of upper-secondary school students. An analysis of the results showed that students could be distinguished into four different groups of solvers based on their total score and solving time: efficient, persistent, impulsive, and inefficient solvers. Utilizing an eye-tracking study, the findings reveal a predominant reliance on symbolic representations, with additional sub-microscopic representations provided by digital applets failing to significantly improve equation-balancing capabilities. This reliance potentially hinders students’ ability to conceptualize reactions at the particulate level, impacting overall chemistry comprehension. This study underscores the need for a pedagogical shift toward integrating multiple representations into chemical education to bridge the gap between procedural skills and deep conceptual understanding. By highlighting the limitations of current teaching approaches and the use of digital tools, this research contributes to improving chemical education strategies, fostering a more integrated and nuanced understanding of chemical principles among students.

This study investigates pre-service chemistry teachers’ ability to interpret data in graphs and tables, justify their responses, and reflect on their performance using a multi-tier diagnostic Graphs and Tables Engagement (GATE) test. A mixed-methods approach involved 55 pre-service teachers from four Czech universities at the start of their studies. The instrument comprised nine tasks across four tiers: content questions, explanation justifications, and associated confidence judgments using a 100 mm visual analogue scale. It showed strong psychometric properties, including high reliability (Cronbach’s alpha = 0.93), satisfactory discrimination indices, and appropriate item difficulty. Students demonstrated moderate data extraction skills (mean Content Score = 0.66) but struggled more with justifications (mean Explanation Score = 0.51), resulting in a Total Score of 0.48. Confidence judgments illuminated cognitive and metacognitive processes: students generally exhibited high confidence in simpler tasks involving direct data retrieval but displayed notable miscalibration in more complex inference-based tasks. Significant differences in confidence between successful and unsuccessful respondents underscored the value of confidence data in distinguishing understanding from guessing. The multi-tier test effectively assessed students’ data interpretation skills but revealed the need for additional qualitative methods – such as eye-tracking, think-aloud protocols, and interviews – to comprehensively understand students’ strategies and guide instructional improvements.

This study focused on pre-service chemistry teachers’ ability to interpret graphical and tabular data - a critical, yet underexplored component of scientific literacy in chemistry education. A newly developed multi-tier diagnostic test was piloted with 21 university students to assess their accuracy, reasoning, and confidence when engaging with visual representations embedded in chemistry learning materials. The results showed that students performed better on graph-based tasks than on those involving tabular data, particularly when higher-order reasoning was required. While confidence judgments generally aligned with performance, metacognitive accuracy decreased for more complex tasks. Psychometric analysis confirmed the test’s high internal consistency and acceptable item discrimination. Based on pilot data and student feedback, the instrument was revised into a four-tier format with enhanced item clarity and cognitive balance. The refined tool will be used in a follow-up study incorporating eye-tracking to further explore students’ interaction with visual data. This research thus contributes to improving diagnostic assessment and instruction in chemistry teacher education.