Question

Which would not cause a change in equilibrium in the following chemical reaction? h2 (g) i2 (g) ⇄ 2hi (g) energy select one:

a. increase temperature
b. increase [ h2 ]
c. decrease [ i2 ]
d. decrease volume

Answer 1

Decreasing the volume of a reaction vessel in the equilibrium reaction of H2(g) + I2(g) ⇄ 2HI(g) increases pressure and shifts the equilibrium toward the side with fewer moles of gas, thereby affecting the equilibrium.

Step-by-step explanation:

In the context of Le Chatelier's principle and chemical equilibrium, several factors can cause a shift in the equilibrium of the reaction H2(g) + I2(g) ⇄ 2HI(g). These factors include changes in temperature, pressure, volume, and the concentration of reactants or products.

Reducing the volume of the reaction vessel would increase the pressure, leading to a shift in the equilibrium. Given that we are dealing with a gaseous equilibria system where equilibrium is described by the relationship Qp = PHI2 / (PH2 PI2), a decrease in volume would result in increased pressures, and according to Le Chatelier's principle, the system would shift toward the side with fewer moles of gas. Since the reaction produces 2 moles of HI for each mole of H2 and I2 consumed, a decrease in volume would shift the equilibrium toward the reactants to reduce pressure, thereby affecting the equilibrium.