# Dynamic equilibrium problem?

Aug 27, 2017

The equilibrium MOVES to the left as written.........

...so $\text{option B}$

#### Explanation:

${N}_{2} {O}_{4} \left(g\right) r i g h t \le f t h a r p \infty n s 2 N {O}_{2} \left(g\right)$

If pressure is increased, the equilibrium should move to the side that RELIEVES pressure; and thus the equilibrium should move to the LEFT as written, inasmuch as the LHS exerts LESS pressure. It moves in this direction so as to maintain the equilibrium and resist the external change.

We can look at this another way, if we can increase pressure such that ${P}_{N {O}_{2}}$ is increased, we also increase the concentration of $\left[N {O}_{2}\right]$, and so it should move left to maintain the equilibrium. Of course, if we add an inert gas to the system, INCREASING the overall pressure, BUT NOT INCREASING ${P}_{N {O}_{2}}$ or ${P}_{{N}_{2} {O}_{4}}$, the equilibrium remains constant....but this was not what we were asked.