Dinitrogen tetraoxide and nitrogen dioxide are two gases that exist in equilibrium at a range of temperatures. NO2 is a reddish brown gas while N2O4 is colorless. ... At High Temperature the red color is strong. ... ... At Low Temperature the gas has less color. ... If we represent the equilibrium as:... 2 NO2(g) N2O4(g) We can conclude that: 1. This reaction is: A. Exothermic B. Endothermic C. Neutral D. More information is needed to answer this question. 2. When the temperature is increased the equilibrium constant, K: A. Increases B. Decreases C. Remains the same D. More information is needed to answer this question. 3. When the temperature is increased the equilibrium concentration of N2O4: A. Increases B. Decreases C. Remains the same D. More information is needed to answer this question.