Equilibrium Question

Question

Of the following equilibria, which one will shift to the left in response to a decrease in volume?

Question 4 options:

	H2(g) + Cl2(g)  2HCl(g)
	2SO3(g)  2SO2(g) + O2(g)
	CO2(g) + H2O(l)  H2CO3(aq)
	N2(g) + 3H2(g)  2NH3(g)
	4Fe(s) + 3O2(g)  2Fe2O3(s)

Answer 1

A strategy is to write the # of moles of gas present on both the reactant and product side. Remember that solids, liquids, and aqueous solutions have no effect on equilibrium state since their activities = 1.

a) 2 mol ↔ 2 mol => Decreasing volume will have no effect on this reaction since moles are equal on reactant & product side.

b) 2 mol ↔ 3 mol => Decreasing volume will shift the reaction to the left (reactant) side since mole reactant < moles product. **answer**

c) 1 mol ↔ 0 mol => Decreasing volume will shift the reaction to the right (product) side since mole reactant > moles product.

d) 4 mol ↔ 2 mol => Decreasing volume will shift the reaction to the right (product) side since mole reactant > moles product

e) 3 mol ↔ 0 mol => Decreasing volume will shift the reaction to the right (product) side since mole reactant > moles product