Understanding metallic bonding: Structure, process and interaction by Rasch analysis

Abstract

This paper reports the results of a survey of 3,006 Year 10-12 students on their understandings of metallic bonding. The instrument was developed based on Chi's ontological categories of scientific concepts and students' understanding of metallic bonding as reported in the literature. The instrument has two parts. Part one probes into students' understanding of metallic bonding as (a) a submicro structure of metals, (b) a process in which individual metal atoms lose their outermost shell electrons to form an sea-electron and octet metal cations, or (c) an all-directional electrostatic force between delocalized electrons and metal cations, that is, an interaction. Part two assesses students' explanation of malleability of metals, for example (a) as a submicro structural rearrangement of metal atoms/cations or (b) based on all-directional electrostatic force. The instrument was validated by the Rasch Model. Psychometric assessment showed that the instrument possessed reasonably good properties of measurement. Results revealed that it was reliable and valid for measuring students' understanding of metallic bonding. Analysis revealed that the structure, process and interaction understandings were unidimensional and in an increasing order of difficulty. Implications for the teaching of metallic bonding, particular through the use of diagrams, critiques and model-based learning, are discussed.

The Model of Educational Reconstruction: Students’ Conceptual Knowledge on Solid State Chemistry Domain

“…Understanding the structure and relating it to nature is a challenge for the students. This is in line with the results of the study conducted by (Cheng & Oon, 2016;Pérez et al, 2017).…”

Students' reasoning about chemical bonding: The lacuna of repulsion

“…Therefore, to align with the literature, we review students' perception of forces in general––attraction or repulsion––in chemical bonding. We grouped students' ideas of chemical bonding based on Cheng and Oon's () categories in understanding metallic bonding and extend them to an understanding of general bonding.…”

“…In such a bonding process, electrons are shared, gained, or lost without referring to the electrostatic forces acting between the atoms. Ionic bonds are seen as a transfer of electrons; covalent bonds involve sharing electron pairs that hold the atoms together (Barker & Millar, ; Pabuçcu & Geban, ; Taber & Coll, ); and atoms in metallic bonds “stick together” to achieve a noble gas configuration (Cheng & Oon, ; de Posada, ; Taber, ). Thus, these students do consider nonmaterial interactions between atoms, but they are poorly understood.…”

“…The third category relates to bonding as the electrical forces between atoms . This category is at the highest level of understanding, as it involves electrostatic forces, which are an intangible interaction between atoms (Cheng & Oon, ). Understanding forces is more challenging: learners generally think of force as a property of a single object rather than as a feature of the interaction between two objects (Driver et al, ).…”

Secondary School Students' Perceptions about Metallic Bond, Metaphors Used in Definition of Metallic Bond and their Analogies

“…Diğer taraftan kimyasal bağlanma başta olmak üzere iyonik, kovalent ve metalik bağların tümü ile ilgili liseden üniversiteye her düzeydeki öğrencinin anlama güçlüğü ve yanlış kavramalara sahip olduğu birçok araştırmacı tarafından bildirilmiştir (Coll & Taylor 2002;Kabapınar & Adik, 2005;Nakiboğlu & Yıldırım, 2019;Taber, Tsaparlis, & Nakiboğlu, 2012). Yapılan çalışmalar incelendiğinde iyonik ve kovalent bağlanma konusunda çok fazla çalışma olmasına rağmen metalik bağlanma konusundaki çalışmaların nispeten sınırlı olduğu görülür (Cheng & Gilbert, 2014;Cheng & Oon, 2016;Coll & Treagust, 2003;de Posada, 1997de Posada, ve 1999Nakiboğlu, 2019;Redfors, 2001;Taber, 2003). Metalik bağlanma, metallerin özellikleri, metalik iletkenlik, yarı iletkenler gibi konularının iyi anlaşılmasında son derece önemli olup öğretilmesi sırasında farklı modeller ve metaforlardan yararlanılır.…”