Question

If the equilibrium constant Kc for the reaction N₂ (g) + O₂(g) ⇌ 2NO(g) is 1.5 x 10⁻³, in which direction will the reaction proceed if the partial pressures of the three gases are all 1.00 x 10⁻³ atm?

Answer 1

If the values of Qc and Kc are equal, the reaction is already at equilibrium and will not shift in any direction.

Step-by-step explanation:

To determine in which direction the reaction will proceed, we need to compare the Qc value with the Kc value. Qc is calculated the same way as Kc, but using the initial concentrations instead of the equilibrium concentrations. If Qc is greater than Kc, the reaction will proceed in the forward direction (from left to right). If Qc is less than Kc, the reaction will proceed in the reverse direction (from right to left).

In this case, Qc can be calculated by substituting the initial partial pressures of the three gases into the expression for Qc. If the partial pressures are all 1.00 x 10^-3 atm, then Qc = ([NO]^2)/([N2][O2]) = (1.00 x 10^-3)^2/((1.00 x 10^-3)^2) = 1.00 x 10^-3.

Since Qc = Kc = 1.5 x 10^-3, the reaction is already at equilibrium. Therefore, the reaction will not shift in any direction, as it is already balanced.