Question

Consider the following system at equilibrium at 573 K: 2NOCl(g) + 18.4 kcal2NO(g) + Cl2(g) If the TEMPERATURE on the equilibrium system is suddenly increased: The reaction must: A. Run in the forward direction to restablish equilibrium. B. Run in the reverse direction to restablish equilibrium. C. Remain the same. Already at equilibrium. The concentration of Cl2 will: A. Increase. B. Decrease. C. Remain the same.

Answer 1

After increasing the temperature of the system:

The reaction must: Run in the forward direction to restablish equilibrium.

Already at equilibrium. The concentration of Cl2 will: Increase.

Step-by-step explanation:

The equilibrium constant, for an endothermic reaction (ΔH ° positive), increases with increasing temperature.

The principle of Le Châtelier indicates that if an equilibrium mixture is heated, and consequently its temperature increases, there will be a net reaction in the direction that counteracts the disturbance caused by the increase in temperature. For an endothermic reaction, the direct reaction absorbs energy in the form of heat.

Consequently, the equilibrium shifts to the side of the products, which means that Kc increases with increasing temperature.