Determination of the E-Z fumaric and maleic acids configuration. An experiment designed to develop scientific research abilities in undergraduates students Determinacion de la configuracion E-Z de los acidos fumarico y maleico. Un experimento orientado a incentivar el desarrollo de la investigacion cientifica en alumnos de pregrado

Bustos C.; Salgado G.; Martínez R.; Carriere, F

Abstract

" In this work we intend to eliminate the idea that laboratory exercises seem like cookbooks. That is, exercises shall be presented as a problematic situation. Based on observation and experimentation, the students should determine the E-Z configuration of maleic and fumaric acids. The basis of this laboratory exercise is the acid-catalyzed isomerization of maleic acid to fumaric acid. Students are given the starting material, reagents and the experimental procedure. They are told that the starting material is a dicarboxylic acid containing a C=C double bond of formula C 4H 4O 4. Students determine melting points, solubilities, acidity and chromatographic patterns for both the starting material and the product, so that a configuration of each acid can be proposed. This type of experiment yields excellent results, because the students are left to deduce that maleic acid is less stable than fumaric acid. Additionally, they conclude that maleic acid is the ""Z"" isomer and fumaric acid is the ""E"" isomer. Finally, this laboratory exercise allows the students to develop simultaneously their critical-thinking skills with the respective laboratory techniques and not to see chemistry as recipes to be followed. "

Más información

Título de la Revista: QUIMICA NOVA
Volumen: 23
Número: 4
Editorial: SOC BRASILEIRA QUIMICA
Fecha de publicación: 2000
Página de inicio: 568
Página final: 570
URL: http://www.scopus.com/inward/record.url?eid=2-s2.0-0347646663&partnerID=q2rCbXpz