Equilibrium constant, Kcfor the reaction
N2 (g) + 3H2 (g) ⇌ 2NH3 (g) at 500 K is 0.061
At a particular time, the analysis shows that composition of the reaction mixture is 3.0 mol L–1 N2, 2.0 mol L–1 H2 and 0.5 mol L–1 NH3. Is the reaction at equilibrium?
If not in which direction does the reaction tend to proceed to reach equilibrium?
The given reaction is:
The reaction quotient (Q) measures the relative amounts of products and reactants present during a reaction at a particular point in time. It also indicates the direction in which the reaction is going to proceed.
Here, 
Where, [NH3]=concentration of NH3 in mol/L at a particular instant
[N2]=concentration of N2 in mol/L at a particular instant
[H2]=concentration of H2 in mol/L at a particular instant
Therefore, 
And Kc=0.061, where Kc is the equilibrium constant.
Since, Qc<Kc, the reaction is not in equilibrium and will proceed in the forward direction in order to attain equilibrium.