Calorimetric studies show that the reaction is exothermic. 2NO2 (g) N2O4 (g) + 14.1 kcal. Based on this information, which one--if any--of the following additional changes would increase the molar concentration at equilibrium of N2O4 (g) ?

Le Chatelier's principle states changes in equilibrium such as factors like temperature and concentration changes. To increase the molar concentration of N2O4 (g), 2NO2 (g) should also increase for equilibrium to occur. Now, this equation is exothermic. By Le Chatelier's principle, equilibrium constant and reaction constants also come into play in terms of increasing or decreasing the temperature.