Which of the following equilibria will shift toward formation of more products if the volume of a reaction mixture at equilibrium increases by a factor of 2? a. 2 so2(g)+ o2(g) 2 so3(g) b. no(g) + o3(g) no2(g) + o2(g) c. 2n2o5(g) 4 no2(g)+ o2(g) d. n2o4(g) 2 no2(g)

        c. 2N₂O₅(g) ⇄ 4 NO₂(g)+ O₂(g), and

        d. N₂O₄(g) ⇄ 2 NO₂(g)

Explanation:

Volume and pressure are inversely related (Boyle's law).

Volume and number of molecules are directly related (Avogadro's principle).

As per Le Chatelier's principle, the reaction will shift toward the side that permits to overcome or minimize the force that disturbs the equilibrium.

With those concepts you can predict which equilibria will shift toward formation of more products if the volume of a reaction mixture at equilibrium increases by a factor of 2

Let's dig into each option.

a. 2 SO₂(g)+ O₂(g) ⇄ 2 SO3(g)

Incorrect.

There are three molecules in the reactant side and two in the product side. so the increase in volume will favor the reverse reaction. This is, the equilibrium will shift to the formation of more reactants, and this is an incorrect choice.

b. NO(g) + O₃(g) ⇄ NO₂(g) + O₂(g)

Incorrect.

There are the same number of molecules in the reactant side and the product side. Hence, the increase of volume will not produce a change in the equlibrium.

c. 2N₂O₅(g) ⇄ 4 NO₂(g)+ O₂(g)

Correct.

There are 2 molecules in the reactant side (left) and four molecules in the product side (right). So, the increase in volume in this system will produce a shift toward the product side.

d. N₂O₄(g) ⇄ 2 NO₂(g)

Correct.

There are more molecules in the product side than in the reactant side, so you predict that the equilibrium will shift toward the formation of more product to overcome the increase of volume.