An Analysis and Improvement of the Experiment about the Effect of Pressure on the Equilibrium of the NO2 - N2O4 System

NO2 - N2O4 사이의 평형에서 압력의 영향에 관한 실험의 문제점 분석 및 개선

  • Published : 2003.06.20


The purpose of this research was to analyze and improve the experiment, observing the color change under compression on the equilibrium of $2NO_2\;{\rightleftarrow}\;N_2O_4$ system, described in high school and general chemistry textbooks. Chemistry textbooks described that the reddish brown color got lighter on the compression of $2NO_2\;{\rightleftarrow}\;N_2O_4$ system. This misinterpretation was due to no consideration of $NO_2$ concentration increase by the volume decrease. In order to propose a correct interpretation, the changes of color and temperature on compression were quantitatively measured and compared with theoretical studies. In addition, an improved experiment, excluding the effect of $NO_2$ concentration increase, was proposed to observe only the color change of the net equilibrium shift.


Equilibrium Shift; $NO_2;\;N_2O_4$ Effect of Pressure


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