Question

10. Nitrogen and oxygen do not react appreciably at room temperature, as illustrated by our atmosphere. But at high temperatures, the reaction below can proceed to a measurable extent. N2(g) + O2(g) ⇔ 2 NO(g) At 3000 K, the reaction above has Keq = 0.0153. If 0.2452 mol of pure NO is injected into an evacuated 2.0-L container and heated to 3000K, what will be the equilibrium concentration of NO?

Answer 1

N2(g) + O2(g) <-------------> 2 NO(g)

0           0                            0.1226

x            x                             0.1226-2x

Kc = (0.1226 - 2x)^2 / x^2

0.0153 = (0.1226 - 2x)^2 / x^2

(0.1226 - 2x) / x = 0.1237

0.1226 - 2x = 0.1237x

x = 0.0577

Equilibrium concentration of NO = 0.00720 M