Abstract:

The relationship between structure and properties has long been regarded as a fundamental concept in science and engineering. However, students face conceptual difficulties when trying to understand this connection. This is even more apparent when the substance is a molecule. The process to predict its properties involves a series of steps and chemical concepts, starting from electron configuration and going through chemical bond, molecular geometry, polarity, etc that are not obvious for many students.

The main goal of this work was to improve the understanding of the relationship between molecular structure and polarity (and therefore properties) and to foster teamwork skills. A learning resource was designed by one of the authors. It consists of a matrix worksheet, which includes all the steps and required concepts to move from electron configuration of atoms to molecular polarity. It is divided into different blocks: atoms, bonds between atoms and geometry and polarity of a molecule. Each block includes several items.

This work describes the design and application of the matrix worksheet in a Chemistry subject for Engineering undergraduates in the University of the Basque Country UPV/EHU. “Chemical Fundamentals of Engineering” is a 9 ECTS credit core module of first year offered currently in Spanish, Basque and English. The first skill of the subject includes to “demonstrate knowledge of the essential principles and theories of the structure of matter to gain understanding of properties and performance of materials” while the forth skill is related to the “ability to work in a team”. By the end of the first semester, students should be able to relate the type of chemical bonding between atoms and the intermolecular forces among the molecules of a substance in order to understand its physical and chemical properties.

This educational material was applied as a learning tool and as an assessment instrument. The carried out activities involved the following: a) formation of working teams giving each group an assignment that required finding out the polarity of a given molecule applying the matrix tool. b) realization of a midterm test including a question about molecular polarity and c) term exam that also assessed the students’ knowledge about the relationship between molecular polarity and properties.

Keywords:

Structure-property relationships, molecular polarity, matrix worksheet.