Question

Given the reaction system in a closed container at equilibrium and at a temperature of 298 K:

Answer 1

Constant. The concentrations must be constant and the rates must be equal.

Answer 2

Answer:

The measurable quantities of the gases at equilibrium must be constant

Explanation:

Measurable quantities for the gases at equilibrium includes rate of formation of $NO_{2}$, rate of formation of $N_{2}O_{4}$, pressure of $NO_{2}$ and pressure of $N_{2}O_{4}$.

At equilibrium, rate of forward reaction is equal to rate of reverse reaction.

Rate of forward reaction infers rate of formation of $NO_{2}$ and rate of backward reaction infers rate of formation of $N_{2}O_{4}$.

As rate of formations from both direction are equal therefore pressure of both gaseous species remains constant.