Contribution of Benchtop NMR Spectroscopy to the Identification of Unknown Liquids Separated by Fractional Distillation

Abstract

Fractional distillation is part of the essential experimental techniques taught to first-year chemistry students, especially during practical organic chemistry work. The characterization of the distillate generally involves measuring the boiling temperature, the refractive index, or the infrared spectrum. In this paper, an unknown mixture composed of two organic solvents is given to the students in order to be separated by fractional distillation and characterized. To perform this task, benchtop 1H NMR spectroscopy was introduced to complement other analytical methods and to familiarize students with this technique while implementing their reasoning abilities.