Question

Dinitrogen and dioxygen combined to form nitrous oxide in equilibrium at 850 K. The equilibrium constant for this reaction is 0.56. If the equilibrium concentration of nitrous oxide gas is 3 × 10^-3 M and both dinitrogen and dioxygen have the same concentration, then what will be the concentration of dinitrogen gas in M?

Options

• 2 × 10^-3

• 16 × 10^-6

• 8 × 10^-6 

• 4 × 10^-3 

Answer 1

4 × 10^-3 

Explanation:

Given reaction is

\[\ce{N2(g) + O2(g) <=> 2NO(g)}\]

Equilibrium constant, `"K"_"C" = (["NO"]^2)/(["N"_2]["O"_2])` and [N₂] = [O₂]

[NO] = `3 xx 10^-3`M

`"K"_"c" = (3 xx 10^-3)^2/(["N"_2]^2)`

0.56 = `(9 xx 10^-6)/(["N"_2]^2)`

[N₂]² = 16 × 10^-6 

∴ [N₂] = 4 × 10^-3 M