The Effect of Temperature on the NO2/N2O4 Equilibrium
Table of contents
Chemical Concept Demonstrated
NO2 is brown and N2O4 is colorless. The intensity of the brown color decreases as the temperature decreases. Therefore, a decrease in temperature yields and increase in N2O4. Equilibrium is shifted to the N2O4 side upon a decrease in temperature.
|Compound||delta H°f (kJ/mol)||delta S° (J/mol-K)|
We can then invoke the assumption that the temperature dependence of delta H° for this reaction is small to estimate the equilibrium constant at various temperatures.
|Temperature||delta G° (kJ)||Kp|
|-78 °C||-22.9||1.3 x 106|
|-196 °C||-43.6||3.7 x 1029|
- Dr. George Bodner (Perdue University)