TCE ForumWhats NewSearchOrders

The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 12 Issue 4 (2007) pp 255-259

The Chemical Equilibrium between Nitrogen Dioxide and Dinitrogen Tetroxide. An Introductory Experiment in Chemical Thermodynamics

Masanori Tesaki, Nobuyoshi Koga,,* Yuko Kawasaki, and Yoshihiro Furukawa

Chemistry Laboratory, Department of Science Education, Graduate School of Education, Hiroshima University, 1-1-1 Kagamiyama, Higashi-Hiroshima 739-8524, Japan,; Department of Biochemistry, Faculty of Science, Okayama University of Science, 1-1 Ridai-cho, Okayama 700-0005, Japan
Received June 9, 2006. Accepted December 5, 2006.

Published online: 4 August 2007

Abstract. A simple experimental procedure using syringes for determining the temperature dependence of the equilibrium constant for the chemical equilibrium between NO2 and N2O4 is proposed as a suitable laboratory activity for an introductory experiment in chemical thermodynamics at universities and colleges. Using their experimental data, students construct fundamental thermodynamic plots, where the relationships among the thermodynamic parameters for the chemical equilibrium can be clearly illustrated. As a result, fairly appropriate values of thermodynamic parameters, for instance, DH0, DS0, and DG0, can be evaluated. On the basis of the thermodynamic parameters, it is possible to make students consider the thermodynamic properties of the dimerization reaction of NO2 to N2O4.

Key Words: Laboratories and Demonstrations; general chemistry; chemical equilibrium; chemical thermodynamics; equilibrium constant; thermodynamic parameters; teaching material

(*) Corresponding author. (E-mail:

Article in PDF format (213 KB) HTML format page numbers updated 9/15/07

Issue date: August 4, 2007

The Chemical Educator 1996-2017