The first purpose of this study was to introduce a laboratory modelling activity focusing on teaching the concepts of radioactive elements/atoms, radioactive decay, and half-life. The second was to investigate pre-service chemistry teachers’ understanding of these concepts. Fifteen pre-service chemistry teachers who had enrolled in a Physical Chemistry Laboratory course participated in the study. The participants simulated the radioactive decay process of an imaginary radioactive element called Cornium during the laboratory modelling activity. In this way, pre-service chemistry teachers were able to visualize and model what is meant by radioactive decay and half-life. Data sources included responses given to open-response conceptual questions, participants’ drawings about radioactive decay and half-life, semi-structured interviews, activity worksheets, and observation notes. Qualitative analysis of data revealed that the pre-service chemistry teachers had misconceptions about the definition of radioactive elements/atoms, radioactive decay, and the half-life process before the activity. The role of the modelling activity in exposing and eliminating these misconceptions was discussed.

中文翻译：

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职前化学老师对放射性衰变的理解调查：一项实验室模拟活动

这项研究的第一个目的是介绍一个实验室建模活动，重点是教授放射性元素/原子，放射性衰变和半衰期的概念。第二是调查职前化学老师对这些概念的理解。参加了物理化学实验室课程的15名职前化学老师参加了该研究。参与者在实验室建模活动中模拟了一种名为Cornium的假想放射性元素的放射性衰变过程。通过这种方式，职前化学老师能够可视化并建模放射性衰变和半衰期的含义。数据来源包括对开放式回答概念性问题的回答，参与者关于放射性衰变的图画以及半衰期，半结构化访谈，活动工作表和观察笔记。对数据的定性分析表明，职前化学老师对放射性元素/原子的定义，放射性衰变以及活动前的半衰期过程有误解。讨论了建模活动在暴露和消除这些误解中的作用。