Abstract:

A careful choice of experiments linking the activities of laboratory courses and the topics of the chemistry curricula is crucial to the development of the physical chemistry curriculum. Here we propose an undergraduate laboratory experiment aimed to explore the thermodynamics of partitioning of relevant molecules between oils and water. Experiments are designed to fit into the undergraduate physical chemistry curriculum and can be easily adapted to a number of different laboratory settings according to the instructor or course requirements. They are part of a broader physical chemistry project aimed to attract student´s attention to real-life (food, environmental, etc.) problems. Particularly, application of the experiments to quantifying molecular partition and solve environmental, pharmaceutical and medical problems is of particularly relevant importance because many relevant molecules, whether natural or synthethic, have target functions which may be largely affected by their location in the different regions of the system.

The proposed experiments involve the use of relevant molecules such as antioxidants, commonly added to foods to minimize lipid oxidation, but can be easily extended to other molecules of interest.

The main learning goals include:
1) analyses of the thermodynamics of partitioning, the role of intermolecular forces and acidity effects
2) use of a variety of physico-chemical measurement techniques for phase separation and product quantification and, and
3) to develop laboratory skills and the ability to work independently by analyzing different ways of controlling the distribution of molecules in multiphasic systems.

Advantages and inconveniences of the methods will be presented as well as alternative experiments specifically designed for undergraduate students taking introductory courses are proposed.

Keywords:

Enhancing Learning and the Undergraduate Experience, Transferring Skills and Disciplines, Curriculum Design and Development.