Let the concentration of N2O at equilibrium be x.
The given reaction is:

Therefore, at equilibrium, in the 10 L vessel:

The value of equilibrium constant i.e. Kc = 2.0 × 10–37 is very small. Therefore, the amount of N2 and O2 reacted is also very small. Thus, x can be neglected from the expressions of molar concentrations of N2 and O2. Then,
