To determine the direction in which the reaction will shift when [tex]\( \text{NO}_2 \)[/tex] is added to the solution, we need to apply Le Chatelier's Principle. This principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to partially counteract the change.
Given the chemical reaction:
[tex]\[
2 \text{NO} ( g )+ \text{O}_2(g) \rightleftharpoons 2 \text{NO}_2(g)+113.06 \, \text{kJ}
\][/tex]
When [tex]\( \text{NO}_2 \)[/tex] is added to the system, we are increasing the concentration of one of the products. According to Le Chatelier's Principle, the system will react to counteract the increase in the concentration of [tex]\( \text{NO}_2 \)[/tex].
An increase in the concentration of [tex]\( \text{NO}_2 \)[/tex] will shift the equilibrium position to the left, favoring the formation of the reactants [tex]\( \text{NO} \)[/tex] and [tex]\( \text{O}_2 \)[/tex]. This shift to the left reduces the impact of adding [tex]\( \text{NO}_2 \)[/tex] by converting some of it back into [tex]\( \text{NO} \)[/tex] and [tex]\( \text{O}_2 \)[/tex].
Therefore, the reaction will shift to the left or towards the reactants.
So, the correct answer is:
A. The reaction shifts left or to reactants.
