Use the reaction 2NO 2 (g) = N 2 O 4 (g) to answer the following question:

What does Le Châtelier's principle predict would happen to the equilibrium conditions if N2 O4 were added to the system?

The equilibrium shifts to the left and more of NO₂ is formed.

Explanation:

The Le Chatelier's principle states that when a form of stress is applied to a system in equilibrium, the system shifts so as to relieve that stress.

This principle explains that addition of one of the reactants to a system in equilibrium leads to the equilibrium shifting in such a way that the reaction occurring reduces the concentration of the added reactant.

In this case the addition of dinitrogen tetraoxide increases its concentration and therefore equilibrium shifts to reduce this concentration.

According to Le Chatelier's Principle, a stress placed on a system at equilibrium will cause the equilibrium to shift to counteract the stress. For example, a temperature increase in the above reaction will favor the reverse reaction to use the excess heat and form brown NO2 gas. A temperature decrease in the above reaction favors the forward reaction to produce heat and form colorless N2O4 gas.